A car is driving on the road. The car starts to decelerate at -3 m/s2. It stops moving after 125 meters. How fast was the car going initially?

27.39 m/s

Explanation:

From the question given above, the following data were obtained:

Deceleration (a) = –3 m/s²

Distance (s) = 125 m

Final velocity (v) = 0 m/s

Initial velocity (u) =?

The initial velocity (u) of the car can be obtained as follow:

v² = u² + 2as

0² = u² + (2 × –3 × 125)

0 = u² + (– 750)

0 = u² – 750

Collect like terms

0 + 750 = u²

750 = u²

Take the square root of both side

u = √750

u = 27.39 m/s

Thus, the initial velocity of the car was 27.39 m/s