Question

A car slams on its brakes, coming to a complete stop in 4.0 s. The car was traveling south at 60.0 mph. Calculate the acceleration.

Answer 1

Answer:

Acceleration, $a=-6.705\ m/s^2$

Explanation:

It is given that,

Velocity of the car, u = 60 mph = 26.82 m/s

Finally it comes to stop, v = 0

Time taken, t = 4 s

We need to find the acceleration of the car. The change in velocity divided by time is called the acceleration of the object. Mathematically, it is given by :

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

$a=\dfrac{0-26.82}{4}$

$a=-6.705\ m/s^2$

Negative sign shows the car is decelerating. So, the acceleration of the car is $6.705\ m/s^2$. Hence, this is the required solution.

Answer 2

Acceleration = ms^(-1)
= 60/4
=15 ms with the power of -1