Physics (AS & A Level) · Feb / March 2025 · Paper 12 · Question 28

The diagram shows a water wave in a shallow tank. The wave is diffracted through a gap in a barrier and spreads. The wavelength of the wave is much smaller than the width of the gap. The wavelength of the wave and the width of the gap are both changed by a small amount. Which combination of changes must increase the amount of spreading due to diffraction?

1. Adecreases / decreases
2. Bdecreases / increases
3. Cincreases / decreases
4. Dincreases / increases

As printed in the paper