An electroscope is a simple device consisting of a metal ball that is attached by a conductor to two thin leaves of metal foil protected from air disturbance in a jar. When the ball is touched by a charged body, the leaves that normally hang straight down, spread apart. Why?

When the same charge spreads in the foil of the electroscope then there is a repulsion between the similarly charged foil.

Explanation:

An electroscope is a device which has metallic foil inside a sealed glass flask preventing in form external environmental disturbances. There is a ball connected to the foil via a conductor.

When the ball is touched by a charged body then the charge is conducted from the body to the ball via conductor to the foils of the electroscope. When the same charge spreads in the foil of the electroscope then there is a repulsion between the similarly charged foil.

When the charge is supplied to any metallic body then it spreads over the surface of the metal so as to minimize the force of repulsion between the similar charges.

another example of kinetic energy would be,

kinetic energy   >     moving energy

answer   >   letter choice (c),   a hammer falling off a table.

hope that !                                         : )