Question

A cricket ball of a mass 500g is moving with a speed of 50 m/s is brought to rest by a player in 0.05s.
Find
i) change in momentum of the ball
(ii) the force applied by the player.​

Answer 1

ANSWER:-

• Change in momentum= -25 kg m/s
• Force applied by the player = -500 N

GIVEN:-

Mass=500 g=0.5 kg

Speed=50 m/s

Time=0.05 s

TO FIND:-

Change in momentum

Force applied by the player

STEP-BY-STEP EXPLANATION:-

Change in momentum=Final momentum-Initial momentum

Initial momentum=0.5×50

==>25 kg m/s

Final momentum=0

Change in momentum=0-25

==>-25 kg m/s

We know:-

F=Change in momentum/Time

F=-25/0.05

F=-500

So the force applied is -500 N

Answer 2

Answer:

-25 Kg.m/s

-500 N

Explanation:

We have,

=> Mass = 500 g = 0.5 Kg

=> Speed (Initial) = 50 m/s

=> Time taken = 0.05 s

To find,

=> Change in momentum.

=> Force applied.

Solution,

Finding the initial momentum:

>> p(initial) = mv

>> p = 0.5 × 50

>> p = 25 Kg.m/s

Finding the final momentum:

>> p(final) = mv

>> p = 0.5 × 0

>> p = 0 Kg.m/s

Change in momentum:

Final momentum - Initial momentum

=> 0 - 25

∴ -25 Kg.m/s

Force applied:

=> F = Change in momentum/Time taken

=> F = -25/0.05

∴ F = -500 N

Since, the force is negative so the force is applied in a direction opposite to the direction of the motion of the ball.