Question

A particle moves according to the law, `x=acos(pit//2).` . What is the distance covered by it in time interval `t=0` to `t=3` second.
A. `2a`
B. `3a`
C. `4a`
D. `a`

Answer 1

Correct Answer - B
Comparing the given equation with `x = a cos omegat`
`:. omega = (pi)/(2)` or `(2 pi)/(T) = (pi)/(2) :. T = 4 sec`
The given time `t = 3` sec is really `(3T)/(4)`
`:.` distance covered will be 3 a