Question

A particle moves in a circle of radius 4 m clock wise at constant speed of $2m{s}^{-1}$. If $\hat{x}$ and $\hat{y}$ are unit vectors along x and y axes, respectively, the centripetal acceleration of the particle at the instant half way between PQ is given by

• A. $-4(\hat{x}-\hat{y})$
• B. $4(\hat{x}+\hat{y})$
• C. $\frac{-(\hat{x}+\hat{y})}{\sqrt{2}}$
• D. $\frac{\hat{x}-\hat{y}}{4}$

Answer 1

The correct option is C $\frac{-(\hat{x}+\hat{y})}{\sqrt{2}}$



$a=\frac{v^2}{r}=\frac{1m}{s^2}$
$\overrightarrow{a}=–acos45\left(\hat{x}\right)–asin45\left(\hat{y}\right)$