With the help of an electroscope, how can we iden-tify the presence and nature of charge on a body?

Explanation

If metal strips in the jar deviate when a body is brought in contact with the metallic disc, then the body is charged. To know the nature of charge on the body, first we must charge the electroscope with known polarity. Then if a body of identical polarity is brought near the metallic disc, we observe increased deviation in metal strips. If it is of opposite polarity, the metal strips collapse or come closer.