Question

A car slows down from speed of 72

km lh to rest in 25 seconds. What is
the acteletaron at the cost in ms-1​

Answer 1

Step-by-step explanation:

Given parameters:

Initial velocity = 72km/hr

Final velocity = 0km/hr

Time taken = 25s

Unknown:

Acceleration = ?

Solution:

To solve this problem, convert km/hr to m/s;

1000m = 1km

3600s = 1hr

72km/hr;

1km/hr = 0.278m/s

72km/hr = 0.278 x 72 = 20.02m/s

Acceleration is the change in velocity divided by the time taken;

Acceleration =
`(final velocity - initial velocity )/(time)`

Acceleration =
`(0 - 20.02)/(25)` = -0.8m/s

The car is actually decelerating at a rate of 0.8m/s