Question

A particle executing SHM has amplitude of 4 cm., and its acceleration at a distance of 1 cm from the mean position is 3 cm$s^{-2}$. Its velocity be when it is at a distance of 2 cm from its mean position is

• A. $2cm/s$
• B. $3cm/s$
• C. $4cm/s$
• D. $6cm/s$

Answer 1

The correct option is D $6cm/s$

$a=-{\omega }^{2}x$
${\omega }^2=3;\omega =\sqrt{3}\frac{rad}{sec}$
$v=\omega \sqrt{A^2-x^2}$
$=\sqrt{3}\times \sqrt{16-4}$
$=\sqrt{3}\times \sqrt{12}=6cm/s$