Question

A car accelerates from rest to 95 km/h in 5 seconds, what is the average acceleration of the car in m/s2

Answer 1

The average acceleration of the car is 5.2778
`(m)/(s^(2) )`

Step-by-step explanation:

The acceleration of an object is a magnitude that indicates how the speed of the object changes in a unit of time. That is, acceleration relates changes in velocity with the time in which they occur.

The expression for the calculation of the acceleration is:

`acceleration=(change of velocity)/(time)`

In this case:

• acceleration=?
• change of velocity= final velocity - initial velocity= 95 km/h - 0 km/h (because the car accelerates from rest)= 95 km/h
• time= 5 seconds

First, it is convenient to express the change in velocity in units of m/s, where 1 h = 3,600 s and 1 km = 1,000 m.

`change of velocity= 95 (km)/(h) =95(1,000 m)/(3,600 s) =26.3889 (m)/(s)`

So, replacing in the definition of acceleration:

`acceleration=(26.3889(m)/(s) )/(5 s)`

acceleration= 5.2778
`(m)/(s^(2) )`

The average acceleration of the car is 5.2778
`(m)/(s^(2) )`