Question

The position vector of a particle is $\overrightarrow{r}=a[\cos \omega t\hat{i}+\sin \omega t\hat{j}]$. The velocity of the particle is

• A. parallel to position vector
• B. directed towards origin
• C. directed away from origin
• D. perpendicular to position vector

Answer 1

The correct option is D perpendicular to position vector

$\overrightarrow{v}=\frac{d\overrightarrow{r}}{dt}=a\omega [-\sin \omega t\hat{i}+\cos \omega t\hat{j}]$

$\because \overrightarrow{v}.\overrightarrow{r}=0⟹velocity\perp positionvector$