Physics (AS & A Level) · Feb / March 2022 · Paper 12 · Question 23

Brief pulses of red, blue and green light are emitted from the Sun at the same time. The pulses travel the same distance to reach Mars. Assume that the pulses travel in a vacuum for the full duration of their journey. In which order would these pulses of light arrive at Mars?

1. Aall arrive at the same time
2. Bblue first, then green, then red
3. Cred first, then blue, then green
4. Dred first, then green, then blue

As printed in the paper