Here is a net experiment that you can perform using your television-set.
Things Required:
Television-set or computer monitor
A sheet of paper
Directions:
Switch on the television-set. Roll up your shirt sleeve. Place your forearm against the television screen. Do you hear anything? Do you feel anything? Slowly, move your arm across the screen. What happens now?
Tear up a sheet of paper into small fingernail-sized pieces. Put these pieces on the television-screen and take your hand away. Do the pieces fall to the floor? Slowly move your hand just above these pieces of paper. Do any of the pieces react? If so, how? Touch several of them. Does this change their behaviour?
This Is What Happens:
The television-screen is a charged surface. As your arm moved along the screen, it entered the electric field of the screen. This field induced a charge on your arm hair so that it might become attracted to the screen. As a result, you felt it standing on end! As the hair approached the screen, the static charge produced a small jump of electricity that made a crackling sound.
Like your arm hair, the pieces of paper became charged by the electric field of the screen. The charge of paper caused it to stick to the screen. When your hand moved above the paper, the charges shifted again to cause the paper to fly off the screen.
