Physics (AS & A Level) · Feb / March 2018 · Paper 12 · Question 26

In a double-slit interference experiment, light of frequency 6.0 × 10¹⁴ Hz is incident on a pair of slits. Bright fringes that are 3.0 mm apart are observed on a screen some distance away. What is the separation of the bright fringes when the frequency of the light is changed to 5.0 × 10¹⁴ Hz?

1. A1.8 mm
2. B2.5 mm
3. C3.0 mm
4. D3.6 mm

As printed in the paper