Optics Question 49
Question: Assertion : A narrow pulse of light is sent through a medium. The pulse will retain its shape as it travels through the medium. Reason : A narrow pulse is made of harmonic waves with a large range of wavelengths.
Options:
A) If both assertion and reason are true and the reason is the correct explanation of the assertion.
B) If both assertion and reason are true but reason is not the correct explanation of the assertion.
C) If assertion is true but reason is false.
D) If the assertion and reason both are false.
E) If assertion is false but reason is true.
Show Answer
Answer:
Correct Answer: E
Solution:
A narrow pulse is made of harmonic waves with a large range of wavelength. As speed of propagation is different for different wavelengths, the pulse cannot retain its shape while travelling through the medium.