PHYSICS Form 4 Form5

Percubaan SPM Selangor fizik Kertas 1 2011

2011-10-14T16:32:00.000+09:00

Selangor fiz K1 2011

soalan percubaan SPM Selangor. Fizik kertas 3 berjawapan

2011-09-24T18:33:00.000+09:00

sesiapa yang ada soalan negeri lain tolong kongsi bersama saya, saya akan upload kan soalan kertas 2 and 1 selepas 29 sep 2011.

Selangor Phy p3 Wit Ans

Interference and refraction

2011-09-17T08:58:00.001+09:00

Diagram below shows the interference pattern of water waves.
Rajah dibawah menunjukkan corak interferen gelombang air.

What happens to the separation between two consecutive nodal lines, x, if the
depth of water in the ripple tank is increased?

Apakah yang akan berlaku kepada jarak pemisahan 2 garisan nodal berturutan, x, jika

kedalaman air dalam tangki riak meningkat?

A. Unchanged / Tidak berubah

B. Increase / Bertambah

C. Decrease / Berkurang

*tips: apply refraction of water wave.

Archimedes' Principle (calculation)

2011-09-16T17:46:00.004+09:00

Pengubahsuain Soalan ke-15 Peperiksaan Percubaan SPM SBP 2011

1. A metal block is immersed in unknown liquid as shown in diagram below. If the liquid pressure exerted on top, P₁and at the bottom, P ₁ are 1.0 x 10⁵Pa and 1.2 x 10⁵ Pa respectively.
Satu bongkah logam direndamkan ke dalam sesuatu cecair seperti ditunjukkan rajah dibawah. Jika tekanan cecair dikenakan pada permukaan atas, P₁ dan permukaan bawah, _P2 adalah masing-masing 1.0 x 10⁵Pa and 1.2 x 10⁵ Pa.

Calculate the buoyant force acting on the metal block?
Hitung daya julangan yang dikenakan ke atas bongkah logam itu?

Ans: 400N

2. A metal block is immersed in water as shown in diagram above.
Satu bongkah logam direndamkan ke dalam air seperti ditunjukkan rajah dibawah.

Calculate the buoyant force acting on the metal block?
Hitung daya julangan yang dikenakan ke atas bongkah logam itu?

Ans: 80 N

Pascal’s Principle

2011-08-17T22:16:00.001+09:00

Pascal’s principle states that when pressure is applied to an enclosed fluid, the pressure will be transmitted equally throughout the whole enclosed fluid.

Pascal’s Principle in Mathematical Expression

Input pressure = output pressure
P₁ = P₂
since
Pressure , P = Force , F / Area , A

therefore
F₂ / A₁ = F₂ / A₂

Explain hydraulic system

• A small input force, F₂ is applied to the small piston resulting in a large output force, F₂.

• Based on the Pascal’s Principle, the pressure is transmitted uniformly in all directions,

• When incompressible fluid is moved through a hydraulic system, the volume through which the input system
moved must be the same as the volume through which the output system,
Hence A₁ d₁ = A₂d₂

• Hydraulic systems acts as a force multiplier. They multiply the input force by a certain factor to gain a larger output force.

• The magnitude of the force at the large piston depends on
(a) the force, F₂, applied to the small piston,

Magnitude of the force = F₂ / F₁

(b) the ratio of the surface area of the piston,

Magnitude of the force = A₂ / A₁

• A hydraulic system must not contain any air bubbles in any position of its hydraulic fluid system. This will reduce the efficiency of the system as part of the applied force will be used up to compress the air bubbles.

Archimedes Principle

2011-08-10T19:55:00.009+09:00

Archimedes’ Principle state that “ When an object is immersed in a fluid (a liquid or a gas) ,the buoyant force
( upthrust force) on the object is equal to the weight of fluid displaced by the object.

From Archimedes’s Principle :

Buoyant Force, Fb = Weight of fluid displace
= mg (note : F = ma)
= ρVg (note : ρ = m/V )

Thus Fb = ρ V g

Where Fb = Bouyant Force or Upthrust
ρ = Density of fluid
V = Volume of fluid displaced or the volume of the object that immersed in the fluid.

Equation for buoyant force

1. Buoyant force = Weight of fluid displaced
2. Buoyant force = ρVg
3. Buoyant force = Weight object in air – weight in water

Actual weight and apparent weight

2011-08-07T14:16:00.002+09:00

Buoyant force makes thing seem to be lighter.

The weight of an object in air is its actual weight
The weight measured when the object is immersed in a fluid is its apparent weight.
The buoyant force is equal to the apparent loss in weight.
The object displaces a volume of water.
The bigger the volume of the object immersed, the bigger the volume of the liquid displaced.

• Volume of liquid displaced = volume of the submerged part of the object.

Work example :

An object weights 2.5 N. When it is fully submerged in a liquid, its apparent weight is 2.2 N.

(a) What is the buoyant force on the object in water?
Tips : Fb= Wc- Wa

(b) What is the weight of water displaced by the object?
Tips : Weight , W = mass, m x gravitational force, g
In SPM take g = 10 Nkg^-1

(c) Determine the volume of water displaced by the object.
[density of water = 1000 kgm^-3]
Tips : Density = mass / volume

(d) What is the volume of the object?
Tips : Volume of liquid displaced = volume of the submerged part of the object.

Buoyant Force

2011-08-05T19:11:00.002+09:00

An object immersed in water is subjected to two forces:
a. the weight of the object which acts downwards, (It pushes the object down)
b. an up-thrust or buoyant force which acts upwards.(it pushes the object up)

If the force from the weight of the object is greater than the force from buoyancy, the object sinks.
Weight , W > Buoyant force, Fb ; object sink

If the buoyant force is greater than the force from the weight of the object, the object floats.

Weight , W < Buoyant force , Fb ; boject float

Jawapan fizik kertas 3 pertengahan tahun 2011

2011-06-14T18:27:00.000+09:00

Marking Schemes Mid Term 2011 P3

Jawapan fizik kertas 2 tingkatan 5 ( pertengahan tahun )

2011-06-13T20:38:00.003+09:00

sila semak jawapan anda dan jumpa saya esok untuk sebarang pembetulan .

answer phyiscs paper 2 form 5 ( midterm 2011)

Free fall

2011-06-10T12:01:00.004+09:00

Objects fall because they are pulled towards the Earth by the force of gravity.

This force is known as the pull of gravity or the earth’s gravitational force.

The earth’s gravitational force tends to pull everything towards its centre.

Free fall
An object is falling freely when it is falling under the force of gravity only.
Objects and people will experience weightlessness during free fall.

Examples of objects not in free fall:

A piece of paper does not fall freely because its fall is affected by air resistance.
Flying birds because there is also an additional force of lift.

Examples of objects in free fall:

An object falls freely only in vacuum. The absence of air means there is no air resistance to oppose the motion of the object. In vacuum, both light and heavy objects fall freely. They fall with the same acceleration ie. The acceleration due to gravity, g.
In a falling elevator.

(gravitational acceleration,g = 9.8 ms^-2, in SPM often approximated g as 10 ms^-2)

s.wg of conductor and resistance

2011-06-09T16:47:00.002+09:00

Diagram 6.1 and Diagram 6.2 show circuits used to investigate the relationship between resistance and cross sectional area of a wire. Constantan wire of s.w.g. 36 and s.w.g 24 with same length are used.
Rajah 6.1 dan Rajah 6.2 menunjukkan litar yang digunakan untuk menyiasat hubungan antara rintangan dan luas keratan rentas dawai. Dawai konstantan s.w.g. 36 dan s.w.g 24 dengan panjang yang sama digunakan.

(a) Using Diagram 6.1 and Diagram 6.2;

Dengan menggunakan Rajah 6.1 dan Rajah 6.2;

(i) Compare the cross sectional area of the constantan wires .

Bandingkan luas keratan rentas dawai konstantan.

(ii) Compare the potential difference across the constantan wires.

Bandingkan beza keupayaan melalui dawai konstantan.

(iii) Compare the magnitude of the current that flow along the constantan wires.

Bandingkan magnitud arus yang mengalir melalui dawai-dawai konstantan tersebut.

(b) Using your answers in 6(b);

Dengan menggunakan jawapan anda dalam 6(b);

(i) Compare the resistance of the constantan wires.

Bandingkan rintangan dawai konstantan.

(ii) Relate the cross sectional area of constantan wire to the resistance of the wire.

Hubungkait luas keratan rentas dawai konstantan dengan rintangan dawai.

(c) What will happen to the reading of voltmeter when another constantan wire s.w.g 36 of the same length is connected parallel to the wire in circuit Diagram 6.1? Explain your answer.

Apakah yang berlaku kepada bacaan voltmeter apabila dawai konstantan s.w.g 36 yang sama panjang dipasang selari dengan dawai dalam litar Rajah 6.1? Jelaskan jawapan anda.

*sewaktu menjawab soalan sebegini, gunakan maklumat yang diberi dan memerhati gambarajah yang sediakan.
*Jawab dengan ayat ringkas .
* tambahan :

Apakah maksud s.w.g ?

http://en.wikipedia.org/wiki/Standard_wire_gauge

Suggested answer.

i) Cross sectional area in Diagram 6.2 is larger than in Diagram 6.1.

ii) Potential difference 6.1 > 6.2

iii) Current for both circuits are the same

i) Resistance 6.1 > 6.2

ii) As the cross sectional area increases, resistance decreases.

c) Reading of voltmeter decreases because total/effective resistance decreases.

Light bulb and resistance

2011-06-08T11:23:00.004+09:00

Diagram shows a bulb labelled 12 V, 24 W.
a. What is meant be 12 V, 24 W.
b. Why filament is made of high resistance conductor.
c. State 2 factors that affected the resistance of the conductor (filament).

Suggested answer :

a. 12 V, 24 W means that the bulb will consume 24 J of electrical energy every second if it is connected to 12 V mains supply.

b. To give out more heat energy and the bulb will become brighter.
(If you connect a bulb to a constant current source, then its brightness increases with increasing resistance, because the power I² R is proportional to the resistance)
c.
i) Length of conductor
The resistance of a conductor increases with length.

ii) Cross sectional area ( thickness) of conductor
The thicker the conductor, the lower the resistance.

iii) Temperature of conductor
Filament light bulbs are non Ohmic conductors,it resistance increases with temperature.
It is a known fact that as an filament light bulb gets hotter, it gets brighter as well.

iv) Material
For fixed length and thickness of a conductor, its resistance is affected by the type of material.
Example resistivity of tungsten is higher than aluminium.

more info : http://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity

Selangor trial Paper 3 q3 (2011)~~heat

2011-05-07T18:12:00.009+09:00

Diagram 3.1 shows a boy accidentally spilt a few drops of hot noodle soup onto his hand and felt slight pain. Later on, he accidentally spilt the whole bowl of hot noodle soup onto himself and felt extreme pain as shown in Diagram 3.2.

Rajah 3.1 menunjukkan mee sup panas terpercik ke atas tangan seorang budak lelaki secara tidak sengaja dan dia merasai sedikit kesakitan. Tidak lama kemudian, sekali lagi secara tidak sengaja dia menumpahkan keseluruhan mee sup yang panas itu ke atas dirinya dan merasai kesakitan yang amat sangat seperti ditunjukkan dalam Rajah 3.2.

Based on the information and observation:
Berdasarkan maklumat dan pemerhatian tersebut:

(a)
State one suitable inference.
Nyatakan satu inferens yang sesuai.

(b)
State one hypothesis that could be investigated.
Nyatakan satu hipotesis yang boleh disiasat.

(c)
With the use of apparatus such as power supply, beaker, immersion heater and other apparatus, describe an experiment to investigate the hypothesis stated in 3(b).
In your description, state clearly the following:

Dengan menggunakan radas seperti bekalan kuasa, bikar, pemanas rendam dan lain-lain
radas, terangkan satu eksperimen untuk menyiasat hipotesis yang dinyatakan di 3(b).
Dalam penerangan anda, jelaskan perkara berikut:

(i)
The aim of the experiment.
Tujuan eksperimen.

(ii)
The variables in the experiment.
Pembolehubah dalameksperimen.

(iii)
list of apparatus and materials.
Senarai radas dan bahan.

(iv)
The arrangement of the apparatus.
Susunan radas.

(v)
The procedure used in the experiment.
Describe how to control the manipulated variable and how to measure the responding variable.
Prosedur yang digunakan dalam eksperimen.
Terangkan bagaimana mengawal pembolehubah dimanipulasikan dan bagaimana mengukur pembolehubah bergerak balas.

(vi)
The way to tabulate the data.
Cara untuk menjadualkan data.

(vii)
The way to analyse the data.
Cara untuk menganalisis data.

Suggested answers:

a. The heat/ time taken of the water depends on its mass/volume
b. The greater the mass/volume, the time taken increase

c .
Aim of the experiment
To investigate the relationship between the time taken and mass/volume

Variables in the experiment
Manipulated variable : mass/volume
Responding variable : Time taken
Constant variable : Initial temperature/specific heat capacity/ changes in temperature

List of apparatus and material
Power supply, thermometer, beaker, immersion heater, stirrer

Arrangement of apparatus

Controlling the manipulated variables
The 20 g of water is filled in the beaker.
The initial temperature, Ө₀, of water is recorded.
The heater is switched on until the water boiled.

Controlling the responding variables
The time taken for the water is observed and recorded/ The heat is calculated.

Repeat the experiment with four different values of mass.
Repeat with masses of boiling water 40 g, 60 g, 80 g and 100 g.

How you tabulate the data.

How you analyse the data.

Exercise Electrical Energy and Power

2011-04-25T23:41:00.004+09:00

1. Two light bulbs labelled as 12 V 36 W and 12 V 6 W respectively are connected in parallel to a 12 V car battery. What is the total amount of heat energy dissipated from the two bulbs in 15 seconds?

Ans : 630J

March test 2011 answer scheme

2011-04-02T13:12:00.005+09:00

Dear my students please check your answer .
Skeme Mar2011 Test

Acceleration and Deceleration (Retardation)

2011-03-18T11:15:00.009+09:00

In the context of linear motion, the direction of the object in motion does not change; but the magnitude of the velocity may change.

When the velocity of an object changes, the object is said to be accelerating.

Acceleration is defined as the rate of change in velocity.

Acceleration is a vector quantity. SI unit for acceleration, a is ms^-2, metre per second squared.

Positive acceleration

If the velocity of an object increases from an initial velocity, u, to a higher final velocity, v.

The acceleration of an object is uniform if its velocity increases at a uniform rate.

Negative acceleration is called deceleration.

If the velocity of an object decreases from an initial velocity, u, to a lower final velocity, v, its acceleration is negative.

The deceleration of an object is uniform if its velocity decreases at a uniform rate.

Zero acceleration

An object moving at a constant velocity, that is, the magnitude and direction of its velocity remain unchanged - is not accelerating; its acceleration is zero.

Quiz :

An object accelerates at a constant rate from rest and reaches a velocity of 10 ms-1 after 5.0 s.

What is it acceleration?

Tips : rest mean stationary ( zero velocity )

Speed of Sound

2011-03-02T21:14:00.000+09:00

The speed of sound, v, in a medium can be determined using the formula v = fλ , whereλ is the wavelength and f is the frequency of the sound wave.

The SI units of v, f and λ are ms^-1 , Hz and metre (m) respectively.

The speed of sound in solids is greater than the speed of sound in liquids which is greater than the speed of sound in gases.

The speed of sound is unaffected by pressure. If the atmospheric pressure changes, the speed of sound in air remains constant.

The speed of sound increases with temperature. At the peak of high-altitude mountains, the speed of sound is less than that at sea level. This is not due to the lower pressures but instead it is because of lower temperatures at the peak of the mountain.

Distance and displacement

2011-02-28T12:41:00.000+09:00

Figure shows a boy cycles from A to B, and then from B to C.

i ) Calculate the distance travelled by the boy and the displacement of the boy.

ii ) Calculate the speed and the velocity of the boy if the boy took 10 s to cycle from A to B and then to C.

iii) then the boy travelled back to A from C, calculate the total distance and displacement travelled by the boy.

Tips to answer this question :

Distance is the actual distance that was covered
Distance depends on the path, from point A --> B --> C in the figure.
Distance (symbol d) does not have a direction, so it is a scalar . It always positive

Displacement (symbol s) is the shortest distance from the starting point to the endpoint.
Distance independent of path taken , from point A to C in the ﬁgure.
Displacement has direction and is therefore a vector. It can be positive or negative

Speed is rate of change of distance. Speed is scalar quantity

Velocity is rate of change of displacement. Velocity vector quantity.

Answer :

Distance from A to B and then to is
3 m + 4 m
= 7 m

Displacement from A to B and then to C is 5 m.

Speed from A to B and then to C
7 m / 10 s
= 0.7 m/s

Velocity from A to B and then to C is
5 m /10 s
= 0.5 m/s.

Distance from A-> B-> C -> B -> C is
3 m + 4 m + 3 m + 4 m
= 14 m

Displacement from A-> B-> C -> B -> C is
5 m - 5 m
= 0 m
( Because the boy's location is the same as his starting location, we use negative sign to indicate opposite direction )

Understanding scalar and vector quantities

2011-02-27T12:22:00.004+09:00

In this unit you should be able to

define scalar and vector quantities
give examples of scalar and vector quantities.

Difference between scalar and vector quantities ,

1. Scalar quantities are quantities that have magnitude but no direction.

2. Vector quantities are quantities that have both magnitude and direction.

Examples of scalar and vector quantities:

Scalar Quantities	Vector Quantities
Distance	Displacement
Speed	Velocity
Work	Acceleration
Area	Force
Length	Momentum

Aktiviti Relief dan skop ujian

2011-02-26T13:08:00.003+09:00

Kepada murid 5 UM dan 5 UKM

Sepanjang 28 Feb 2011- 7 March 2011, cikgu ada bertugas di Stadium Kelana Jaya, jadi sila buat latihan dan nota sampai chapter 2.2. sekiranya ada masalah sila hugungi cikgu di FB.

Ujian March hanya meliputi Chapter 1 wave . Soalan adalah dalam bentuk struktur dan essai, peruntukan masa adalah 1 jam 30 min.

Sediakan kertas test pad, pembaris, mesin kira, pensil , jangka lukis ( compesses) dan alat tulis yang sesuai semasa ujian.

tidak dilupakan, 5 % markah ujian termasuk nota dan latihan yang anda buat.

Electromagnetic (EM ) waves

2011-02-12T10:48:00.015+09:00

Electromagnetic wave is a self-propagating wave in space with electric and magnetic components.

These components oscillate at right angles to each other and to the direction of propagation, and are in phase with each other.
Electromagnetic wave is classiﬁed into types according to the frequency of the wave:
these types include ( order of decreasing frequency)

gamma rays, X-rays, ultraviolet radiation,visible light, infrared radiation, microwaves and radio waves.

source : http://www.t-lea.net/spectrumSURA.html

Nature of EM wave:

Show characteristics of polarisation.
transverse wave.
since EM waves are transverse wave it do not require a medium to propagate and can travel in vacuum.
EM wave still a wave so energy is transferred by the wave.
obey the wave equation v = f λ .
in a vacuum, the waves travel at the speed of light c = 3 x 10 ⁸ ms ^-1
undergo reflection, refraction, diffraction and interference .
electrical neutral.

Examples of some uses of electromagnetic waves :

Gamma rays - sterilisation of equipment.
X-ray - radiography ( X-ray photograph )
ultraviolet - identification of counterfeit notes.
Visible light - sight
infrared - night vision, thermal imaging .
microwave - cooking, radar system , satellite transmission ( example : Astro satellite TV, GPS..)
Radio waves - telecommunication , communication.

Quiz:

1. Explain how an EM wave propagates, with the aid of a diagram.
2. What is the speed of light? What symbol is used to refer to the speed of light? Does the speed of light change?

3. Do EM waves need a medium to travel through?

Sound waves

2011-01-24T21:47:00.001+09:00

1. What is sound?

Sound is a form of energy propagated as waves that make our eardrums vibrate.
Sound waves are caused by vibrating objects.
Sound waves are longitudinal waves.

2. How is sound produced by a vibrating objects?

Sound waves are produced when a vibrating object causes the air molecules around it to vibrate.
When a tuning fork vibrates, layers of air vibrate and the sound energy is propagated through the air around it in the form of waves.
When the tuning fork moves forwards, the air is compressed.
When the tuning fork moves backwards, the air layers are pulled apart and cause a rarefaction.
Therefore, a series of compression and rarefactions will produce sound.

3.Why does sound waves is a longitudinal waves?

The air particles vibrate backward and forward in the direction parallel to the direction of propagation of the sound wave.

4. Explain how the loudness relates to amplitude

The loudness of the sound depends on its amplitude.
If the amplitude is increased, the loudness increases.

5. Explain how the pitch relates to frequency

A high pitch sound corresponds to a high frequency and a low pitch sound corresponds to a low frequency of vibration.

6.

The reflection of sound is called echoes.

i) Ultrasound waves (higher than 20 000 Hz) is used to scan and capture the image of a fetus in a mother’s womb.

ii) Sonar is the technique of using ultrasound to locate underwater objects or to measure the depth of a seabed.

Learn more :

http://en.wikipedia.org/wiki/Sonar
http://library.thinkquest.org/19537/Apps2.html
http://animals.howstuffworks.com/mammals/bat2.htm

Damping and resonance in an oscillating system

2011-01-23T09:39:00.002+09:00

Damping and Resonance in an oscillating system

Damping simulation :
Click this link http://www.myphysicslab.com/spring1.html to find out effect of damping to energy, velocity and acceleration of the system.
set Y as position ( displacement of load), X as responding variables. Observe the pattern of the graph.

When damping occurs in an oscillating system, energy is lost to the surroundings, causing the amplitude of the oscillation to decrease.

When resonance occurs, the frequency of the forced vibration is equal to the natural frequency of the system. this causes the system to vibrate at maximum amplitude.

Virtual Lab in You-tube

1. Barton's Pendulum
2.Resonance

Quiz: Choose the correct answer.

1.
A system vibrates with a natural frequency. If a forced vibration of the same frequency is given to the system, what will happen ?

Tips : The forced vibration is the same as the natural frequency of the system .

a. Damping
b. Resonance
d. Natural frequency
d. Vibration

2. When does an oscillating system experience damping ?
a. when the amplitude of the oscillation decreases.
b. when the period decrease.
c. when the frequency increases.
d. when the amplitude remains constant.

3. Which of the following graphs shows greater damping effect?

Significant Figure

2011-01-20T01:04:00.001+09:00

In measurement, significant figures relate the certainty of the measurement.
As the number of significant figures increases, the certainty of the measurement increase, which means we are more certain about what we have measured.
In the SPM syllabus, the magnitude of a physical quantity is usually rounded up to 3 or 4 significant figures.

Example:
speed of light in a vacuum = 299 792 458 ms ^-1

= 3.00 × 10⁸ ms^-1 (to 3 significant figures)

learn more form Form 4 Modern Mathematics .

Polish my skills:

Write your answer in 3 significant figures
1. The mass of insect is 0.006 g
2. The height of Petronas Twin Towers is 452 000 mm
3. The total area of Malaysia is 329750 km²

Standard form

2011-01-16T20:12:00.002+09:00

It is impossible to do Physics without mathematics, therefore you need to polish your rusty mathematics skill .

Some physical quantities have extremely large magnitudes.
These extremely large and small values can be written in standard form ( scientific Notation ) so that it is neat, simple and easy to read.

Example :
a) Diameter of the earth is
= 130 000 000 metres
= 1.3 x 10⁷

b) Length of Paramyxoviruses
= 0.000014 m
= 1.4 x 10^-5

Polish my skills :

Write the following quantities in standard form :

a. The length of virus = 0.00 000 008 m
b. Red light wavelength = 0.00 000 067 m
c. the mass of a ship = 75 000 000 kg

1.1 Understanding Physics

2011-01-13T18:26:00.014+09:00

In physics, we study natural phenomena and the properties of matter.
The aim of physics is to explain the fundamental nature of the universe by using the concept of physics.
Physics involves the conduct of studies and experiments to find answers to the question ‘Why?’and ‘How?’ in relation to the mysteries of the universe.
The majority of natural phenomena can be explained using the principles of physics, for example;
i) Shadows are formed because light travel in straight line.
ii) Black objects are black because almost all the light that falls on them is absorbed.

Fields of study in physics

Force and motion - investigates the action of force and motion.
Forces and pressure- pressure, pressure in liquids, gas pressure, atmospheric pressure, Pascal’s principle, Archimedes’ principle, Bernoulli’s principle.
Heat- Studies the influence of heat on different types of matter.
Light - explains the different phenomenon due to light.
Electricity and electromagnetism- investigates the interactions of electric and magnetic fields.
Electronics - studies the use of electronic devices in various field.
Waves - understands the properties of different types of waves and their uses.

I Know it :

The following diagrams show some of the natural phenomena and occurrences around us. Find out the related field of study in Physics.

1.

Car racing .
Field: _____________
2.

Cooking.
Field :______________

3.

Communication using mobile phone.
Field : ________________

4.

Shadows show ( Wayang Kulit )
Field: _________________

REFRACTION OF WAVES

2011-01-01T19:39:00.010+09:00

Definition :

Refraction of waves is a change in its direction as the waves pass from one medium to another.
It occurs when there is a difference in the speed of the wave at the boundary of two mediums.

What happens after refraction of wave?
The wave has the same frequency, but a different speed, wavelength and direction of propagation.

example :
1.Water waves passes from deep water to shallow water
The wave has the same frequency, but speed decrease, wavelength decrease and the the water wave is refracted toward the normal.

2. Water waves passes from shallow water to deep water
The wave has the same frequency, but speed increase, wavelength increase and the the water wave is refracted away from the normal.

Refraction phenomena :
1. A swimming pool seems much shallower than it actually is.
2. The sound of a moving car at a distance is clearer at night than that in the day time. This is due to the effects of the refraction of sound waves.

Relationship between frequency, speed and wavelength .
v = f λ ( the wave frequency remain unchanged)
∴ v ∝ λ
f ₁ = f₂

v₁ = v₂
λ ₁ . λ ₂

Quiz :
1.
A plane wave has a wavelength of 2 cm and a velocity of 8 cm s^-1 as it moves over surface of shallow water. When the plane wave moves into an area of greater depth, its velocity becomes 12 cm s^-1. What is
(a) the wavelength
(b) the frequency
of the wave in the area of greater depth?

Happy New year 2011

2010-12-31T14:43:00.003+09:00

Reflection of waves

2010-12-22T10:03:00.011+09:00

Reflection of a wave occurs when a wave strikes an obstacle. The wave undergoes a change in direction of propagation when it is reflected.

The phenomenon of reflection of waves obeys the Law of reflection where:

The angle of reflection is ~~not~~equal to the angle of incidence.
The incident wave, the reflected wave and normal lie in the same plane which is perpendicular to the reflecting surface at the point of incidence.

Characteristics of reflection of waves:

The wavelength , speed and frequency of the reflected waves is the same as that of the incidence.
Angle of incidence = angle of reflection.
Direction of propagation of wave changes.

Application of reflection of waves:

Radar system
Makeup mirror
Car rear mirror and side mirror for your safety .
Optical fibre
Ultrasonic
Fishing with sonar.
Seawall to deflected the energy of the waves from the coast.

Seawall

Fishing with sonar

Displacement- Time graph and displacement -Distance Graph for a wave

2010-12-20T19:06:00.002+09:00

The sinusoidal graph shown is a graph of displacement, s against time , t of a load on a spring.

O is called the equilibrium position.

From a displacement-time graph for a wave, we can obtain
i) amplitude, a ,and
ii) period, T.

From a displacement- distance graph for a wave, we can obtain
i) amplitude, a ,and
ii) wavelength, λ

Relationship between Speed, (v) Wavelength,(λ) and Frequency (f)

The speed of a wave is determined by its wavelength, λ, and its frequency, f , according ti the equation V= f λ

For a wave moving at constant speed, increasing the frequency will result in a decrease in the wavelength.

For a wave moving at constant speed, decreasing the frequency will result in an increase in the wavelength.

Work example:

What is the frequency of water waves with the wavelength of 3.0 cm and traveling at a speed of 1.5 cm/s ?

solution :

Step 1: write formula first
V= f λ

step 2 : Substitute all given info into formula
1.5 cm/s = f x 3.0 cm

Step 3:find unknown
f = 0.5 Hz

Wave Properties

2010-12-08T17:40:00.003+09:00

In merupakan bab pertama dalam syllabus tingkatan 5. Murid 5 UM dan 5UKM anda diminta membuat kuiz yang disediakan. Sebarang pertanyaan boleh ditulis pada Cbox atau hantar ke Facebook saya.

1. Waves are produced by vibrating systems.

Vibrating systems

2. Waves transfer energy. Waves that travel through a medium transfer energy without transferring matter.

3. In transverse waves, the direction of waves propagation is perpendicular to the direction of vibration of the particles.
Example: water waves, light waves and electromagnetic waves.

4. In longitudinal waves, the direction of wave propagation is parallel to the direction of vibration of the particles.
Longitudinal waves need a medium to propagate. This type of waves cannot propagate through a vacuum.
Example: a sound wave.

5. A wavefront is an imaginary line representing all parts of a wave in which particles are vibrating in the same phase and have the same distance from the source.
The direction of propagation of waves is always perpendicular to the wavefront.

6. Amplitude, a, is the maximum displacement from the equilibrium position.

7. Period, T, is the time required to make one complete oscillation.

8. Frequency, f, is the number of complete oscillations made in one second.

9. Wavelength, is defined as the distance between two consecutive points that are in phase.

( i ) For a transverse wave, wavelength can be measured as the distance from one crest and also the distance from one trough to the next trough.
(ii ) For a longitudinal wave, wavelength can be measured as the distance between
two consecutive compressions or two consecutive rarefactions.

Password : fizik

Wave Properties » Fun Trivia Maker

Gred SPM mulai 2009

2010-12-03T09:44:00.004+09:00

Berikut merupakan gred SPM yang mula diperkenalkan mulai 2009.

SPM Candidates All the Best!

SPM tips ~ paper 2 ( light )

2010-11-29T15:57:00.017+09:00

Diagram 9.1 and Diagram 9.2 show light rays from two identical objects passing through two identical convex lenses. Both lenses produce real images. F is the focal point for the lens.
Rajah 9.1 dan Rajah 9.2 menunjukkan sinar cahaya dari dua objek yang serupa melalui dua kanta yang serupa. Kedua-dua kanta tersebut menghasilkan imej nyata. F adalah titik fokus untuk kanta tersebut.

(a)
(i)
Name the phenomenon involved. [1 mark]
Namakan fenomena yang terlibat. [1 markah]

Hits for solving the problem :
Refraction of light is the bending of light ray at the boundary as it travels from one medium to another.
Reflection of light occurs when the light ray strike the surface of mirror.

ii)
Observe Diagram 9.1 and Diagram 9.2. Compare the object distance, the image distance, the size of the image and the power of the lens. Relate the size of the image with the object distance. [5 marks]

Perhatikan Rajah 9.1 dan Rajah 9.2. Bandingkan jarak objek, jarak imej, saiz imej dan kuasa kanta. Hubungkaitkan saiz imej dengan jarak objek. [5 markah]

Hits for solving the problem :

Pay attention to the marks allocated. the marks usually indicates the number of points required.

Understand the task

Compare the object distance,
Compare the image distance,
Compare the size of the image
Compare the power of the lens.
Relate the size of the image with the object distance.

(b)
Diagram 9.3 shows the structure of a simple camera.
Rajah 9.3 menunjukkan struktur sebuah kamera ringkas.

(i)
Explain how the camera is able to capture the image of a distant object. [3 marks]
Terangkan bagaimana kamera boleh merakam imej suatu objek jauh. [3 markah]

Hits for solving the problem :

Pay attention to the marks allocated , the marks usually indicates the number of points required

(ii)
State the range of the object distance where the image formed is sharp. [1 mark]
Nyatakan julat jarak objek bagi kedudukan imej yang tajam. [1markah]

(c)
A student is given two convex lenses, R and S. The focal length for R and S are 20 cm and 5 cm respectively. Suggest and explain how to build a microscope which produces a sharp and magnified image based on the following aspects:

Seorang pelajar diberi dua kanta cembung R dan S. Panjang fokus untuk R dan S adalah 20 cm dan 5 cm masing-masing. Cadang dan terangkan bagaimana anda membina sebuah mikroskop yang menghasilkan imej yang tajam dan dibesarkan berdasarkan aspek-aspek berikut:

Hits for solving the problem :
Underline the important information given in the question, such as focal length for each lens, build a microscope...

(i)
Arrangement of lenses
Susunan kanta

(ii)
Position of object
Kedudukan objek

(iii)
Position of the first image
Kedudukan imej pertama

(iv)
Distance between the two lenses
Jarak antara kedua-dua kanta

(d)
Suggest two modifications that need to be done to the microscope to produce a bigger final image. [2 marks]

Cadangkan dua ubahsuaian yang perlu dibuat pada mikroskop untuk menghasilkan imej akhir yang besar .[2 markah]

Hits for solving the problem :
M= Mo x Me

SPM Trial MARA 2010 ~ paper 2 ( waves )

2010-11-28T14:58:00.012+09:00

Diagram 8.1 shows Aini trying to open the house’s front gate using a remote control. Even though Amin is blocking her, the gate can still be opened.
Rajah 8.1 menunjukkan Aini cuba membuka pintu pagar rumah dengan menggunakan alat kawalan jauh. Walaupun Amin menghalangnya pintu pagar masih boleh dibuka.
(a)
(i)
Name the wave phenomenon involved
Namakan fenomena gelombang yang terlibat.

ii)
On Diagram 8.2, draw the wave pattern based on the situation in Diagram 8.1.

(b)
Table 8.1 shows the characteristics of three waves, X, Y and Z to be used in the remote control for the gate. Calculate the wavelength of each wave.
Jadual 8.1 menunjukkan ciri-ciri untuk tiga gelombang, X, Y dan Z yang akan digunakan dalam alat kawalan jauh bagi pintu pagar. Hitungkan panjang gelombang bagi setiap gelombang.

(i)
Wave X
Gelombang X

(ii)
Wave Y
Gelombang Y

(iii)
Wave Z
Gelombang Z

(c)
(i)
Based on your answers in 8(b), which wave is the most suitable to be used in the remote control for the gate?
Berdasarkan jawapan anda di 8(b), gelombang manakah yang paling sesuai digunakan untuk alat kawalan jauh bagi pintu pagar itu?

(ii)
State one reason for the answer in 8(c)(i).
Nyatakan satu sebab bagi jawapan 8(c)(i).

(d)
Based on the values of the wave speed shown in Table 8.1,
Berdasarkan nilai laju gelombang dalam udara yang ditunjukkan dalam Jadual 8.1,

(i)
Predict what wave X is.
Ramalkan gelombang X.

(ii)
State one application for wave X.
Nyatakan satu kegunaan gelombang X.

Suggested answer:

a)
i) Diffraction of waves
ii)

b)
i) Velocity = Frequency × Wavelength
3.3 x 10 ² = 4. 0 x 10⁵ x wavelength
wavelength = 8.25 x 10 ^-3 m

ii) wavelength = 0.75m

iii) wavelength = 7.5 x 1o ^-11

c) i) wave Y

ii) The e of effect diffraction is very obvious.

d)
i) Sound wave

ii)Disintegration of kidney stones // Locating an object under water // remove plaque from teeth

SPM Trial MARA 2010 ~ paper 2 ( Resistance )

2010-11-27T16:58:00.008+09:00

Diagram 6.1 and Diagram 6.2 show two electric circuits each consisting of a copper wire.
Rajah 6.1 dan Rajah 6.2 menunjukkan dua litar elektrik masing-masing mengandungi seutas wayar kuprum.

(a)
Name the quantity measured by the ammeter.
Namakan kuantiti yang diukur oleh ammeter.

Hits for answer the problem :
Key words " quantity"

(b)
(i) Compare the thickness of the copper wire in Diagram 6.1 and Diagram 6.2.
Bandingkan ketebalan wayar kuprum dalam Rajah 6.1 dan Rajah 6.2.
(ii)
Compare the ammeter reading in Diagram 6.1 and Diagram 6.2.
Bandingkan bacaan ammeter dalam Rajah 6.1 dan Rajah 6.2.

(iii) Relate the thickness of the copper wire to the ammeter reading.
Hubungkaitkan ketebalan wayar kuprum dengan bacaan ammeter .

(iv)
Relate the thickness of the copper wire to its resistance.
Hubungkaitkan ketebalan wayar kuprum dengan rintangan.

(c)
You are provided with three light bulbs labelled A, B and C labelled A, B and C as shown in Diagram 6.3.
Anda dibekalkan dengan tiga mentol Anda dibekalkan dengan tiga mentol berlabel A, B dan C seperti dalam Rajah 6.3. seperti dalam Rajah 6.3.
Draw and label an electric circuit connecting all the three bulbs in which all the bulbs should light up with normal brightness connected to a power supply of 240 V alternating current . Add switches to the circuit.
Lukis dan label satu litar elektrik yang menyambungkan ketiga-tiga mentol di mana semua a mentol seharusnya menyala dengan kecerahan normal apabila disambungkan kepada bekalan kuasa 240 V arus ulang-alik. Tambahkan suis pada litar anda.

Suggested answers:

a) Electric current

b)
i) Thickenss of the copper wire of diagram 6.2 thicker than diagram 6.1.

ii) Ammeter reading in diagram 6.1 is less than diagram 6.2.

iii) The thicker the copper wire, the higher the ammeter reading.

iv) The thicker the copper wire, the lower the resistance.

c)

SPM Trial MARA 2010 ~ paper 2 ( Thermal Equilibrium )

2010-11-26T13:57:00.015+09:00

Question 5

A student carries out an activity to record the temperature change of oil and water. Both liquids are heated by identical heaters for two minutes. The initial temperature of oil and water are 30oC.
Seorang pelajar membuat aktiviti untuk merekod perubahan suhu minyak dan air. Kedua cecair dipanaskan oleh pemanas yang serupa selama dua minit. Suhu awal minyak dan air adalah 30oC.

(a) Name the condition in which the temperature of the water is equal to the temperature of the thermometer.
Namakan keadaan di mana suhu air adalah sama dengan suhu termometer.

Hits for answer the problem :
Key words " temperature of the water is equal to the temperature of the thermometer."

(b)
Observe Diagram 5.1 and Diagram 5.2. Compare,
Perhatikan Rajah 5।. dan Rajah(b) 5 .2. Bandingkan

(i) the mass of oil and mass of water.
jisim minyak dan jisim air.

Hits for answer the problem :
Observe the compression balance indicator //scale.

(ii) the temperature change in oil and also in water.
perubahan suhu minyak dan suhu air.

Hits for answer the problem :
Observe the thermometer .

(c)
(i) Compare the amount of heat supplied by the heater to the oil and to the water.
Bandingkan jumlah haba yang dibekalkan oleh pemanas kepada minyak dan kepada air.

Hits for answer the problem :
key words "Both liquids are heated by identical heaters for two minutes"

(ii) Compare the amount of heat absorbed by oil and water.
Bandingkan jumlah tenaga yang diserap oleh minyak dan air.

Hits for answer the problem :
Assuming that no heat lost to the surroundings,

heat received by liquids = heat given out by the heater.

Q=mcӨ = Pt

(iii) Name the physical quantity that will explain the comparison you made in 5(b)(ii).
Namakan kuantiti fizik yang menerangkan perbandingan yang dibuat dalam 5(b)(ii).

(d)
If the heating time is increased to 5 minutes, will there be any change in the physical quantity in (c)(iii)? Explain your answer.
Jika tempoh pemanasan ditambah kepada 5 minit, adakah sebarang perubahan pada kuantiti fizikal pada (c)(iii)? Terangkan jawapan anda

Suggested answers:

a) Thermal Equilibrium

b)
i)Mass of the oil and water are same .
ii)Temperature of oil is higher than temperature of water

c)
i) Heat supplied by the heater to the oil is equal to heat supplied to the water
ii) The amount of heat absorbed by oil and water are same .
iii) Specific heat capacity

d)
When two objects of equal masses are heated at equal rates, the object with the smaller heat capacity will have a faster temperature increase.

The specific heat capacity of oil is smaller than water, therefore oil show higher temperature.

SPM Trial MARA 2010 ~ paper 2 ( Impulsive force )

2010-11-17T18:43:00.007+09:00

Question 2

Diagram 2 shows a baseball player wearing a soft thick glove to catch a ball during a baseball match.

Rajah 2 menunjukkan seorang pemain bola lisut memakai sarung tangan tebal yang lembut untuk menangkap bola semasa pertndingan bola lisut.

(a) What is meant by impulsive force?

Apakah maksud daya impuls?

(b) The ball of mass 0.15 kg moves with a velocity of 20 m s when it is hit.

Calculate the impulsive force acting on the glove when the time of impact is 8.0 x 10 ^-2 s.

Bola berjisim 0.15 kg bergerak dengan kelajuan 20 m s apabila dipukul.

Hitungkan daya impuls yang bertindak ke atas sarung tangan jika masa tindakbalas 8.0 x 10^-2 s.

(c) Compare the impulsive force if the baseball player wears a hard glove to catch the ball. Explain your answer.
Bandingkan daya impuls yang di hasilkan jika pemain itu menggunakan sarung tangan yang keras untuk menangkap bola. Jelaskan jawapan anda.

Hits for answer the problem :
Decreasing the time of impact will increase the magnitude of the impulsive force, and vice versa.

SPM Trial MARA 2010 ~ paper 2 ( Water tank )

2010-11-16T21:14:00.009+09:00

Question 7

Diagram 7 shows a public water tank which supplies water for domestic use to a residential area.

Rajah 7 menunjukkan sebuah tangki air awam yang membekalkan air untuk kegunaan domestik di satu kawasan perumahan.

(a)

State one factor which affects pressure in a liquid.

Nyatakan satu faktor yang mempengaruhi tekanan dalam cecair.

Hits for solving problem :

Liquid pressure increase with depth//height, and increase with density.

(b)

Based on Diagram 7, calculate the water pressure at X.

(Density of water = 10³ kg m^-3).

Berdasarkan Rajah 7, hitungkan tekanan air di X.

( Ketumpatan air =10³ kg m^-3).

Hits for solving the problem:

~ list all info given or underline the importance information given.

Given ρ, g ,h and find P .

~ state the formula, P = ρ g h

~ substitute the value for each quantity

~ answer with the correct unit.

(c)

Tenants on the fifth floor of the apartment block are unable to obtain tap

water. Why?

Penghuni di tingkat lima blok pangsapuri tidak menerima bekalan air paip. Mengapa?

(d)

Suggest and explain modifications to the water distribution system shown in Diagram 7, to ensure the following :

Tangki air itu tidak dapat memenuhi keperluan semua penghuni di blok pangsapuri lima tingkat. Cadang dan terangkan pengubahsuaian yang perlu dilakukan untuk setiap yang berikut:

(i)

Sufficient water supply for all area residents.

Bekalan air yang mencukupi untuk semua penghuni kawasan.

(ii)

Water supply reaches the fifth floor of the apartment building.

Bekalan air boleh sampai ke tingkat lima blok pangsapuri.

The public water supply system often faces a problem in delivering water to water tanks located on tall buildings.

Suggest and explain one other way to overcome this problem.

Sistem bekalan air awam kerapkali menghadapi masalah untuk menyalurkan air ke tangki

air yang berada di bahagian atas bangunan tinggi.

Cadangkan dan jelaskan satu cara lain untuk mengatasi masalah ini.

Hits for solving problem (c) - (e):

In prublic water supply system, the water is pumped up to a water tank located higher than the building in that area.

Due to the gravitational pull, water in the storage tank is maintaned at a high pressure and enables water to flow to the lower area ( consumers )

Suggested answers:

a) The height of water tank.

P = ρ g h

= 1000 x 10 x 10

= 100 000 N/ m

= 100 000 Pa

Water tanks are tall to provide pressure.

The location of fifth floor apartment is exceed the height that the tank's water pressure can handle.

i) Build a larger water tank,to holds enough water for all area residents.

ii) Ensure water tank located higher than apartment , to provide the necessary pressure.

e) Install a pump to provide pressure.

SPM Trial MARA 2010 ~ paper 2 ( CRO )

2010-11-15T18:07:00.014+09:00

Question 4

A cathode ray oscilloscope ( C. R. O) is an instrument that converts electronic and electric signals to a visual display.

Diagram 4.1 shows the structure of a simple cathode ray oscilloscope (CRO).
Rajah 4.1 menunjukkan struktur satu osiloskop sinar katod ringkas (OSK) .

(a) (i) Based on Diagram 4.1, name the component T.
Berdasarkan Rajah 4.1, namakan komponen T.

Hints for solving the problem (ii) and (iii) :
The process of emission of electrons from the surface of a heated metal is known as thermionic emission.

This is because some of the electrons have gained enough kinetic energy to break free from the metal surface and escape to the surroundings.

(ii) Explain what happens to the electrons on the surface of T when T is heated.

Terangkan apa yang berlaku kepada elektron pada permukaan T jika T dipanaskan.

(iii) Name the physics process in (a)(ii).
Namakan proses fizik yang berlaku dalam (a)(ii).

(b) A student uses a CRO to study the output voltage of a bicycle dynamo. The time-base is set at 100 ms/division and the Y gain control is set at 0.5 V/division.

Seorang pelajar menggunakan OSK untuk mengkaji voltan output yang dijana oleh sebuah dinamo basikal. Dasar masa telah dilaraskan pada 100 ms/bahagian dan gandaan Y dilaraskan pada 0.5 V /bahagian.

Hits for solving the problem:

(i) Calculate the frequency of the wave produced by the bicycle dynamo.
Hitungkan frekuensi gelombang yang dihasilkan oleh dinamo basikal.

Hits for solving the problem:
f = 1/ T

(ii) On Diagram 4.2, draw a new trace to show the voltage output if the frequency of the dynamo is doubled.

Pada Rajah 4.2, lukiskan surihan yang baru untuk menunjukkan voltan output jika frekuensi dinamo digandakan.

Suggested answers:

(i) Cathode

(ii)Cathode or T emits electrons when it is heated.

(iii) Thermionic emission

(i) time taken to complete one oscillation , T = 4 x 100 ms

T= 400 ms

Frequency , f = 1 / T

f = 1/ 400 ms

f = 2.5 Hz

(ii)

Tips for Physics Paper 1 and paper 2

2010-11-14T09:17:00.000+09:00

Paper 1

1. Cancel or mark (x) which is wrong option then choose.

2. Always refer the formula given on formula list.

( one step calculation only because 1 question = 1 mark)

3. Blacken each finished answer immediately.

Paper 2

1. Definition of the term in Physics. ( please refer to text book)

Force, work, power, momentum, inertia, impulsive force, coherent, pressure, temperature and heat...

2. The principle in Physics and application.

Force in equilibrium, thermal equilibrium, Pascal's principle, conservation of momentum.

3. The Law in Physics and application.

Hooke's Law, Ohm's Law, Charles Law, Boyle's Law, Newton"t first law, Newton Second Law...

4. Drawing skills ( Use pencil, ruler and other suitable drawing tools)

Total internal reflection, ray diagram, interference , field circuit, refraction of wave, circuit...

5. Graph skills

Axis, plotting, scale, straight or curve line, gradient , extrapolation.

Decision Making - - Hydraulic jack

2010-11-11T23:16:00.008+09:00

Diagram shows a hydraulic jack in a car service centre.

Table below shows four type of hydraulic oil, K, L, M and N , with different specifications. You are required to determine the most suitable hydraulic oil to run the hydraulic jack.

Study the specifications of all four types of hydraulic oil from the following aspects:

i ) Boiling point of the hydraulic oil

ii) Specific heat capacity of the hydraulic oil

iii) Density of hydraulic oil

iv) Rate of vaporisation of hydraulic oil

Suggested answer:

i) Has high boiling point

~ so that hydraulic fluid not easily boiling

ii) Has higher specific heat capacity

~ so that it can't be easily became hot

iii) Has lower density

~ so the hydraulic oil is not heavy

iv) Has lower rate of vaporisation

~ Volume of the hydraulic oil not easily vaporise.

Hydraulic oil L is chosen

Reason :

L has high boiling point, higher specific heat capacity, lower density and lower rate of vaporisation .

Structure question -( concave mirror)

2010-11-09T22:07:00.010+09:00

Percubaan SPM MRSM 2010

Diagram 1 shows an object placed in front of a mirror.
Rajah 1 menunjukkan satu objek diletakkan di hadapan sebuah cermin.

(a) Name the type of mirror shown in Diagram 1.

Namakan jenis kanta yang digunakan dalam Rajah 1.

Hints for solving the problem :

A convex mirror curves outwards.

A concave mirror curves inwards.

(b) Draw the image in the box given in Diagram 1.

Lukiskan imej dalam petak yang disediakan pada Rajah 1.

Hints for solving the problem :

Draw the image with its tail on the axis. The head is where the two reflected rays meet.

convex mirror typically make a virtual image.

A virtual image is shown using a dotted line.

Berdasarkan Rajah 1. tandakan pada pernyataan yang betul mengenai imej yang terbentuk.

[] The image can be formed on a screen.

[] Imej boleh terbentuk pada skrin.

[] The image cannot be formed on a screen.

[] Imej tidak boleh terbentuk pada skrin.

Hints for solving the problem :

Real image can be displaced on a screen.

Virtual image can be seen by the observer but not be displaced on a screen.

(d) What happens to the size of the image if the object is placed at X?

Apakah yang terjadi pada saiz imej jika objek diletakkan pula di X ?

Hints for solving the problem :

The image appears larges in size when the object is nearer to the convex mirror.

Suggested answers:

(a) Convex mirror

(b)

(c)The image cannot be formed on a screen.

(d) Image is smaller than original size

Happy Deepavali

2010-11-01T18:21:00.000+09:00

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Tip- SPM Fizik kertas 3

2010-10-28T18:12:00.012+09:00

A student investigate how the extension of a spring changes with the load acting on a spring.

Diagram 1.1 and 1.2 show what happens when two different loads are hang on two identical springs.

Based on the information and the observation above:
Berdasarkan maklumat dan pemerhatian di atas:

a) State one suitable inference that can be made
Nyatakan satu inferens yang sesuai [1 mark]

* pesanan :
baca soalan dengan teliti dan carikan pembolehubah yang tersurat dalam maklumat yang diberi.
Contohnya pemboleh ubah boleh laras ( manipulated variable ) ialah beban load // force // mass) yang digunakan , dan pemboleh ubah bersandar ( responding variable) ialah pemanjangan spring. ( extention of spring ).

Sambungkan pemboleh ubah yang dikesan dengan kata kunci seperti
i) MV influences RV
ii) RV is influenced by MV
iii) RV depends on MV.

b) State one appropriate hypothesis for an investigation
Nyatakan satu hipotesis yang sesuai dikaji [1 mark]

* pesanan :
Tuliskan hubungan MV dengan RV .

c) With the use of apparatus such as a spring, slotted weights and other apparatus, describe an experimental framework to test your hypothesis stated in 2(b)
In your description, state clearly the following:

Menggunakan alat radas seperti spring, jisim berslot dan lain-lain radas yang sesuai, terangkan suatu rangka kerja eksperimen untuk menguji hipotesis anda di 3(b).
Dalam penerangan anda, jelaskan perkara-perkara berikut

(i) The aim of the experiment
Tujuan eksperimen

* pesanan :
Gunakan kata kunci
i) to study...
ii) to investigate...

(ii) The variables in the experiment
Pembolehubah didalam eksperimen

* pesanan :
senaraikan ketiga-tiga pemboleh ubah.

(iii) The list of apparatus and materials

Senarai radas dan bahan

* pesanan :

Alatan yang dicadangkan perlu disaling semula, dan pastikan alatan yang disenaraikan boleh digunakan untuk menguju MV dan RV yang anda cadangkan.

Contoh:

Pembaris (Meter rule ) --> mengukur panjang spring.

(iv) The arrangement of the apparatus

Susunan radas

* pesanan :

Lukiskan dan labelkan susunan radas yang berfungsi.

(v) The procedure of the experiment which include the method of controlling the manipulated variable and the method of measuring the responding variable.

Prosedur eksperimen termasuk kaedah mengawal pembolehubah dimanipulasi dan kaedah mengukur pembolehubah bergerakbalas

* pesanan :

Senaraikan arahan menguju MV dan RV, dicadangkan arahan mengulangi ujikaji sebanyak 4 kali .

(vi) The way you would tabulate the data

Cara untuk menjadualkan data

* pesanan :

Lakarkan jadual berlabel dan tandakan unit kuantiti fizikal.

(vii) The way you would analyse the data

Cara untuk menganalisis data [10 marks]

*pesanan:

Lakarkan graf dengan tandakan MV (di paksi-x) dan RV ( dipaksi-y) pastikan unit yang betul diberi.

Suggested answer:

a) Inference :

The pulling force influences the extension of the spring//

The length of spring is influenced by the pulling force//

Length of spring depends on the force acting on it.

b) Hypothesis:

The bigger the force , the longer the spring.//

When the force(mass) increases, the length of the spring increase

i) Aim:

To investigate the relationship between force //mass and the extension of the spring

ii)

Manipulated variable : Force, F// mass

Responding variable: Extension of spring, x

Fixed variable: Diameter// stiffness of spring/ the initial length, lo/ spring constant of spring,k

iii) List of apparatus/ materials :

Spring, pin, slotted weight, retort stand with clamp, meter rule and plasticine.

iv) Arrangement of the apparatus( with labels )

~ Method of controlling the manipulated variable :

1. Determine the initial length, lo, without any slotted weight hung to the spring.

2. Hang a slotted weight of mass 50 g, (force/weight of 0.5 N) and measure the length of the spring .

~Method of measuring the responding variable :

3. Calculate the extension of the spring, x using the formula ( length l) – (initial length, lo)

~Repeating :

4. Repeat the experiment using mass of 100g, 150g, 200g and 250g (or force, F= 1.0 N, 1,5 N, 2.0 N and 2,5 N)

vi)

Selamat Maju Jaya.

SPM Trial MARA 2010 ~ paper 2 ( Radioactivity )

2010-10-25T17:43:00.018+09:00

Question 3

Diagram 3 shows a Geiger-Muller tube (GM tube) and a rate meter which are used to detect the level of milk in containers in a factory.

Table 3 shows the readings recorded by the rate meter for four containers P, Q, R and S when a radioactive source is placed near the containers. The rate meter records a reading of 100 counts per minute when there is no radioactive source nearby.

Rajah 3 menunjukkan sebuah tiub GM dan alat meter kadar digunakan untuk mengesan paras susu di dalam bekas di sebuah kilang.

Jadual 3 menunjukkan bacaan meter kadar bagi empat bekas P, Q, R dan S bila suatu sumber radioaktif diletakkan berhampiran bekas. Meter kadar mencatatkan bacaan 100 bilangan per minit jika tiada sumber radioaktif diletakkan berdekatan.

(a)

Name the radiation emitted by the radioactive source.

Namakan sinar radiasi yang dikeluarkan oleh sumber radioaktif itu.

Hints for solving the problem :
Beta or gamma source are used, depending on the thickness and the density of the material to be measured.

(b)

(i)

Based on Table 3, which container has the least amount of milk?

State one reason for your answer.

Berdasarkan Jadual 3, bekas yang manakah mempunyai kuantiti susu paling kecil?

Beri satu sebab bagi jawapan anda.

Hints for solving the problem :

The reading depends on the milk quantity in the container and it gets higher as the milk is under level.

(ii)

State the actual rate meter reading for Q.

Nyatakan kadar bacaan sebenar bagi Q

Hints for solving the problem :

When there is no radioactive source nearby the detector detect natural background radiation . (cosmic radiation, solar radiation, etc)

seconds. Calculate its half-life.

Jisim suatu sumber radioaktif menyusut dari 80.0 g kepada 20.0 g dalam masa 30 saat.

Hitungkan setengah hayat bagi bahan radioaktif tersebut.

Hints for solving the problem :
The half-life of a radioisotope is the average time it takes for half of the remaining radiative atoms to decay to a different atom.

Suggested answers:

a) beta because it can penetrate box and liquid and is less
dangerous than gamma.
b)
(i) R has the least a mount of milk. highest mean it allow more beta to passes though.
(ii) 566 - 100 = 466 counts per second
c) 80 --> 40 --> 20
it undergo 2 half-life.
half life = 30/ 2 = 15 secs