CAPE Physics Unit 2 · 2013 · Paper 1 · Question Q38

Which statement about the behaviour of the oil drops during the experiment is correct?

1. (A)When an oil drop becomes charged, the size of the charge must equal e.
2. (B)When an oil drop is stationary, it must carry a charge.
3. (C)When an oil drop moves upwards, only the electric force is acting on it.
4. (D)When no electric field acts, all drops move downwards with the same constant velocity.

This question uses a figure or table from the paper — you'll see it when you practise.