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										HOW THE ELECTROSCOPE WORKS
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															A comb that has been negatively charged (by passing it several times through hair) is brought near the loop of the electroscope. Electrons (negative charges) in the loop are repelled down to the leaves. Each leaf now has more negative charges than positive, so the leaves repel each other. Meanwhile, the loop is left with a positive charge.
			The electroscope is neutral. The foil leaves hang freely because they have the same number of positive and negative charges.
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					3.
																Removing the comb now imparts a negative charge to the entire electroscope (the scope is charged). Since that includes each leaf, the excess electrons in the leaves keep them spread because, as you know, negative charges repel each other.
				When the comb makes contact, electrons rush from the comb onto the loop (opposite charges attract). The leaves remain apart; they still have an excess of electrons with nowhere to go and nothing to do but repel one another.
																	How do you discharge the scope? Simply touch the loop with any conductor, like your finger. This allows the excess electrons to flow into the conductor, thus rendering the electroscope neutral and dropping the leaves.