Question

A positively charged electroscope has separated leaves.
a. Suppose you bring a positively charged rod close to the top of the electroscope, but not touching. How will the leaves respond?

Answer 1

I think they will get close to each other until the rod is taken away.

Answer 2

Because the rod will polarize the top of the electroscope.

Answer 3

Actually I think they will remain the same since there is a net + charge on the elec.

Answer 4

The positively charged rod will cause the following:

1) Since unlike charges attract - negative charges in the electroscope will be pulled up towards the rod (and out of the leaves)

2) Since like charges repel - positive charges in the electroscope will be pushed away from the rod (and into the leaves)

The result of the above is that the leaves will become more positively charged and therefore spread out more.