A car slows down from a speed of 20m/s to rest in 25 seconds.Find its acceleration.

it lost 20m/s in 25 seconds. So, each second it lost 20/25=0.8 m/s

a = -0.8 m/s^2

To find the acceleration of the car, we need to use the formula:

acceleration = (final velocity - initial velocity) / time

Given:
Initial velocity (u) = 20 m/s (the speed at which the car starts slowing down)
Final velocity (v) = 0 m/s (the car comes to rest)
Time (t) = 25 seconds

Substituting the values into the formula, we get:

acceleration = (0 - 20) / 25

Now, let's do the calculation:

acceleration = -20 / 25
acceleration = -0.8 m/s²

Therefore, the acceleration of the car is -0.8 m/s². The negative sign indicates that the car is slowing down, as the velocity decreases.