Electric fields

An electric field is the region in which an electric charge experiences a force

Activity to observe the pattern of electric fields:
When the power supply is turned on, the talcum powder will map the electrical field lines.

• Sesame oil is used because it conducts electricity only at extremely high potential difference
• The density of the field lines represent the intensity of the electric field
  

Simulation : http://www.vias.org/simulations/simusoft_efield.html

Natural phenomena == Lightning

IMAGE SOURCE http://www.ux1.eiu.edu/~jpstimac/1400/shockinglecture.html

During cloud formation, the friction of movement creates a lot of excess charge. This induced positive charges on the objects below it.
If the forces of attraction are strong enough, the negative charges in the clouds will be attracted towards the positive charges of the objects, resulting in lightning.