Physics (AS & A Level) · Oct / Nov 2020 · Paper 12 · Question 31

A molecule behaves as an electric 'dipole' consisting of two equal point charges of opposite sign, separated by a fixed distance. The molecule moves with constant horizontal velocity as it enters a vertical uniform electric field, as shown. The positive and negative charges of the molecule enter the field at the same time. What describes the effect of the electric field on the velocity of the molecule?

1. Ahorizontal component of velocity: constant; vertical component of velocity: increases
2. Bhorizontal component of velocity: constant; vertical component of velocity: zero
3. Chorizontal component of velocity: increases; vertical component of velocity: increases
4. Dhorizontal component of velocity: increases; vertical component of velocity: zero

As printed in the paper