Physics (AS & A Level) · May / June 2023 · Paper 11 · Question 28

A laser produces a beam of light of wavelength 650 nm. The beam is incident normally on two slits that are a distance of 0.12 mm apart. A screen is placed parallel to the slits. The bright interference fringes on the screen have a separation of 7.5 cm. What is the distance between the screen and the two slits?

1. A1.4 m
2. B2.8 m
3. C7.0 m
4. D14 m

As printed in the paper