Physics - Rotation Question with Solution | TestHub

Angular velocity =$\omega$
Linear velocity =$v$
Length of string = Radius =$r$

If string is halved,$r^{\text{'}}=\frac{r}{2}$
Angular momentum,$L=r\times p$
where,$r$= radius vector
and p = linear momentum
$=r\times mv\mathrm{}\left[\because \theta ={90}^o\right]$
$=mvr$
As L remain constant,
$mvr$= constant
$\Rightarrow$If$r^{\text{'}}\to \frac{r}{2^{\text{'}}}{v}^{\text{'}}=2v$such that
$m{v}^{\text{'}}{r}^{\text{'}}=m2v\times \frac{r}{2}$
Hence, linear velocity will be 2 v.