wave-optics Question 11
Question: Q. 2. In a Young’s double-slit experiment, the source is white light. One of the holes is covered by a red filter and another by a blue filter. In this case,
(a) there shall be alternate interference patterns of red and blue.
(b) there shall be an interference pattern for red distinct from that for blue.
(c) there shall be no interference fringes.
(d) there shall be an interference pattern for red mixing with one for blue.
[NCERT Exemplar]
Show Answer
Solution:
Ans. Correct option : (c)
Explanation: For sustained interference, the source must be coherent and should emit the light of same frequency.
In this problem, one hole is covered with red and other with blue, which has different frequency, so no interferende takes place.
Very Short Answer Type Questions
(1 mark each)
[AI Q. 1. Define the term ‘coherent sources’ which are required to produce interference pattern in Young’s double slit experiment.
R [Delhi Comptt. I, II, III 2014]
Ans. Two monochromatic sources, which produce light waves, having a constant phase difference, are known as coherent sources.
[CBSE Marking Scheme 2014]
