Question

. A car accelerates uniformly from 0 to 72 km/h in 11.5 seconds.

a) What is the acceleration of the car in m/s2? b) What is the position of the car by the time it reaches the velocity of 72 km/h?​

Answer 1

Step-by-step explanation:

First job is to convert 72 km/hr to m/s:

`72(km)/(hr)` ×
`(1000m)/(1km)` ×
`(1hr)/(3600s)` = 2.0 × 10¹ m/s

Now to find the acceleration which is

`a=(v_f-v_0)/(t)` and filling in:

`a=(2.0*10^1-0)/(11.5)=1.7(m)/(s^2)` That's part a. Part b want to know how far the car can get in 11.5 seconds (because that's the time it takes for the car to get to 72 km/hr). Since we know that the car can get 2.0 × 10¹ meters in 1 second, that means that in 11.5 seconds, the car can get 11.5(2.0 × 10¹) which is 230 meters.