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3 years ago

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A tennis player smashes a ball of mass m horizontally at a vertical wall. The ball rebounds at the same speed v with which it st

ruck the wall. Has the momentum of the ball changed, and if so, by how much?
A. 4mv
B.0
C.mv
D.0.5mv
E.2mv

1 answer:

Morgarella [4.7K]3 years ago

5 0

Answer:

<em> B.0</em>

Explanation:

Change in momentum: This is defined as the product of mass and change in velocity of a body. or it can be defined as the product of force and time of a body. The fundamental unit of change in momentum is kg.m/s

Change in momentum = M(V-U)......................... Equation 1

where M = mass of the ball, V = final velocity of the ball, U = initial velocity of the ball.

Let: M = m kg and V = U = v m/s

Substituting these values into equation 1

Change in momentum = m(v-v)

Change in momentum = m(0)

Change in momentum = 0 kg.m/s

<em>Therefore the momentum of the ball has not changed.</em>

<em>The right option is B.0</em>

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Explanation:

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From the free body diagram we can now do a sum of forces in the x and y direction. Let's start with the y-direction:

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so now we solve for theta. We can start by factoring mg so we get:

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we can divide both sides into mg so we get:

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