Question

A solid cylinder of mass $m$ and radius $r$ is rolling with angular speed $\omega$ on a horizontal plane. The magnitude of its angular momentum about origin $O$ is

• A. $m{r}^2\omega$
• B. $1.5m{r}^2\omega$
• C. $2m{r}^2\omega$
• D. $2.5m{r}^2\omega$

Answer 1

The correct option is B $1.5m{r}^2\omega$

$Accordingtoquestion.....Netangularmomentumabout0=MvR+I\omega v=R\omega ,I=\frac{M{R}^2}{2}L=M\left(R\omega \right)R+\left(\frac{M{R}^2}{2}\right)\omega \Rightarrow M{R}^2\omega +\left(\frac{M{R}^2}{2}\right)\omega =\left(\frac{2M{R}^2+M{R}^2}{2}\right)\omega \Rightarrow \left(\frac{3M{R}^2}{2}\right)\omega \therefore 1.5M{R}^2\omega sothatthecorrectoptionisB.$