A 2-kg bowling ball is accidentally dropped from a window and strikes the sidewalk at a speed of 30 m/s. It bounces back up with an initial speed of 20 m/s from the sidewalk. What is the magnitude of the impulse the sidewalk imparts to the bowling ball

Explanation:

Given:

mass of the ball,

initial speed of the ball before collision,

final speed of hte ball after collision,

We have mathematical relation for  impulse as:

......................(1)

From the Newton's second law of motion:

................................(2)

where:

time duration

change in velocity

change in momentum

Now from (1) & (2)

(since this impulse is due to the impact force of the ball falling on the ground)

putting the values

is the impulse transfer to the bowling by the sidewalk.

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.

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the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia