A particle moves along the curve

PHYSICS · Single correct · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

y=\frac{x^2}{2}

. Here

x

varies with time as

x=\frac{t^2}{2}

, where

x

and

y

are measured in metres and

t

in seconds. At

t=2\text{ s}

, the velocity of the particle in

\text{m s}^{-1}

is: (1)

4\hat{i}+6\hat{j}

(2)

2\hat{i}+4\hat{j}

(3)

4\hat{i}+2\hat{j}

(4)

4\hat{i}+4\hat{j}