# Worksheet: Multiple-Slit Interference

In this worksheet, we will practice calculating the light intensities of different wavelengths at variable angles relative to the transmission axis of multiple slits.

**Q4: **

Ten narrow slits are equally spaced 0.25 mm apart and illuminated with yellow light of wavelength 580 nm.

What is the angular position of the third principal maximum?

What is the angular position of the fourth principal maximum?

What is the separation of the third and fourth principal maxima on a screen 2.0 m from the slits?

- A m
- B m
- C m
- D m
- E m

**Q8: **

Forty-one narrow slits are equally spaced and separated by 0.290 mm. The slits are illuminated by blue light of wavelength 400 nm. The twenty-fifth secondary maximum of the interference pattern produced is observed.

What is the angular position of this maximum?

What is the ratio of the peak intensity of this maximum to that of the primary maximum?