Question

When a ball of ‘5’ kg strikes a wall with a velocity ‘20’m/s and rebounds at the same velocity then find the change in momentum of the ball.​

Answer 1

When a ball of ‘5’ kg strikes a wall with a velocity ‘20’m/s and rebounds at the same velocity then find the change in momentum of the ball.

Weight of ball = 5 kg

Velocity = 20 m/sec

Momentum = ?

V1 = -20 m / sec { - vc because it's downward }

V2 = +20 m/ sec { + vc because it's upward }

Change in momentum , ∆ P

∆ P = m ( V2 - V1)

=> ∆ P = (5) [ 20 + 20 )] kg m/sec .

=> ∆ P = ( 5) ( 20+20) kg m/ sec .

=> ∆ P = 200 kg m/ sec .

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