Question

A car traveling at 15 m/s starts to decelerate steadily. It comes to a complete stop in 5 seconds. What is its acceleration ?

Answer 1

Answer:

$-3m {s}^{-2}$

Explanation:

The initial velocity, u, of the car=15m/s

The final velocity, v, of the car =0m/s

Time, t, taken for the car to come to a stop=5s

Acceleration is calculated by,

$a= \frac{v - u}{t}$

By substitution,

$a= \frac{0- 15}{5}$

$a= \frac{- 15}{5}$

$a = -3 {ms}^{ - 2}$

The negative sign implies that the car has decelerated.