Physics (AS & A Level) · May / June 2017 · Paper 13 · Question 31

Two metal plates are a distance of 30 cm apart in a vacuum. A current exists between the two plates consisting of electrons moving at a constant speed of 1.5 × 10^6 m s^–1. At any instant, there is always just one electron travelling between the plates. What is the current between the plates?

1. A3.2 × 10^–26 A
2. B8.0 × 10^–13 A
3. C1.6 × 10^–12 A
4. D2.0 × 10^–7 A

As printed in the paper