Question 30
What happens when waves pass through a gap equal to their wavelength?
A There is diffraction and the wavelength decreases.
B There is diffraction and the wavelength stays the same.
C There is no diffraction and the wavelength decreases.
D There is no diffraction and the wavelength stays the same.
Reference: Past Exam Paper – November 2018 Paper 12 Q28
Solution:
Answer: B.
When the gap is equal in width to the wavelength of the wave, diffraction occurs. [C and D incorrect]
During diffraction, the wavelength stays the same as the wave has not changed medium. It has only passed through a gap. The distance between wavefronts remains constant. [B is correct]
No comments:
Post a Comment