wave_mechanics mock_test_waves_and_acoustics Question 7
Question: When beats are produced by two progressive waves of nearly the same frequency, which one of the following is correct?
Options:
A) The particles vibrate simple harmonically, with the frequency equal to the difference in the component frequencies.
B) The amplitude of vibration at any point changes simple harmonically with a frequency equal to the difference in the frequencies of the two waves.
C) The frequency of beats depends upon the position, where the observer is.
D) The frequency of beats changes as the time progresses.
Show Answer
Answer:
Correct Answer: B
Solution:
[b] As $ y=A _{b}\sin (2\pi n _{av}t) $ where $ A _{b}=2A _{b}\cos (2\pi n _{A}t) $ where $ n _{A}=\frac{n _{1}-n _{2}}{2} $ Hence, the amplitude of vibration at any point changes simple harmonically with a frequency equal to the difference in the frequencies of the two waves.
BETA
