Question

car moves in a velocity of 54 km/h find the velocity in m/s​

Answer 1

Intial velocity of car, u = 54 km/h = 54 × 5/18 m/s

u = 15 m/s

Car stops on applying brakes 20m

Displacement is covered by car ,S = 20m

finally car stops ∴ final velocity of car , v = 0

Now, use formula

V² = u² + 2aS , here a is Acceleration

⇒ 0 = (15)² + 2 × a × 20

⇒ -225 = 40a

⇒ a = -5.625 m/s² [ here negative sign shows that acceleration is opposite direction of motion of car ]

Hence, magnitude of acceleration = 5.625 m/s²

Answer 2

54×5/18 = 15 km/s

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