Question
Physics Question on wave interference
When a compact disc (CD) is illuminated by small source of white light coloured band are observed. This is due to
A
Interference
B
Scattering
C
Reflection
D
Diffraction
Answer
Diffraction
Explanation
Solution
Diffraction is the bending or spreading of waves around obstacles or through openings. In the case of a CD, it has a series of closely spaced tracks or grooves on its surface. When white light hits the CD, the grooves act as diffracting elements that cause the light to spread out and interfere with each other. This interference results in the appearance of colored bands or a rainbow-like pattern.
So, the correct answer is (D) diffraction.