Question

The displacement `y` of a particle executing periodic motion is given by `y = 4 cos^(2) ((1)/(2)t) sin(1000t)`
This expression may be considereed to be a result of the superposition of
A. two
B. three
C. four
D. five

Answer 1

Correct Answer - B
`y=4 cos^(2)((t)/(2))sin 1000t`
`=2 "cos"(t)/(2)[sin(1000+(1)/(2))t+sin(1000-(1)/(2))t]`
`=sin1001 t+sin1000t+sin 1000t+sin 999t`
`=sin 1001t+2 sin 1000t+sin 999t`