A car is moving with a velocity 54 km/ h on a straight road stops on applying brakes after covering a distance of 20 m compute the acceleration of the car.
(please explain in detail)
:)))))
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Answer:
A car is moving with a velocity 54 km/ h on a straight road stops on applying brakes after covering a distance of 20 m compute the acceleration of the car.
(please explain in detail)
:)))))
✳️ Initial velocity with which the car was moving (u) = 54 km/h = 15 m/s
✳️ Final velocity (v) = 0 km/h, because ultimately, i.e., finally the car has stopped due to application of brakes which means its velocity comes to zero ultimately.
✳️ Distance covered (S) = 20 m
✳️ Acceleration (a) = ?
We know the equation, v²-u² = 2aS (where, symbols have their usual meanings)
Putting the values of the known quantities, we get :
(0)²-(15)² = 2.a.20
=> -225 = 40.a
=> a = -225/40 m/s² = -5.625 m/s²
If you see carefully, then you will observe that the acceleration of the car is negative, i.e., -5.625 m/s², a negative value. This negative sign actually represents negative acceleration which is often called as retardation. This negative acceleration means that there is a decrease in velocity with respect to time interval.