A particle moves along a straight line

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

Problem

A particle moves along a straight line. Its position at any instant is given by

x=32t-\frac{8t^3}{3}

, where

x

is in metres and

t

is in seconds. Find the acceleration of the particle at the instant when it is at rest. (1)

-16\text{ m/s}^2

(2)

-32\text{ m/s}^2

(3)

32\text{ m/s}^2

(4)

16\text{ m/s}^2