Wave Mechanics Beats Question 5
Question: A tuning fork sounded together with a tuning fork of frequency 256 emits two beats. On loading the tuning fork of frequency 256, the number of beats heard are 1 per second. The frequency of tuning fork is
[NCERT 1975, 81; MP PET 1985]
Options:
A) 257
B) 258
C) 256
D) 254
Show Answer
Answer:
Correct Answer: D
Solution:
nA = Known frequency = 256, nB = ? x = 2 bps, which is decreasing after loading (i.e.
x¯) known tuning fork is loaded so nA¯ Hence nA¯ ? nB = x¯ …
(i) Correct nB ? nA¯ = x¯ …
(ii) Wrong
Therefore nB = nA ? x = 256 ? 2 = 254 Hz.
BETA
