Question

A particle had a velocity of $18m/s$ in the right direction and $2.4s$ later its velocity was $30m/s$ in the opposite direction. What was the acceleration of the particle during this $2.4s$ interval?

• A. $-5m/s^2$
• B. $-10m/s^2$
• C. $-15m/s^2$
• D. $-20m/s^2$

Answer 1

The correct option is D $-20m/s^2$

Initial Velocity, $u=18m/s$

Final Velocity, $v=-30m/s$

Acceleration, $a=\frac{v-u}{t}$
$=\frac{-30-18}{2.4}=-20m/s^2$