Question

A ball of mass 400 gram is dropped from a height of 5 M. A boy on the ground hits the ball vertically upward with a bat with an average speed of hundred Newton so that it at end of vertical height of 20m the time for which the bowl remains in the contact with the bat.

Answer 1

Hello! brother,

Here goes your answer..

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Given mass=400gm

                  ⇒0.4kgs.

And we'll consider the first height [h1]=5meters

                               The second height[h2]=20meters.

and gravity remains to 10m/sec².(As they haven't given certain gravity number)

Now,Velocity(U) of the ball after dropping from a height=5m

         Velocity (V) of the ball after got hit by bat.

From formula,U²=2gh1⇒U=√{2×10×5}⇒10m

                       V²=2gh2⇒V=√{2×10×20}⇒20m

Now Impulse=m{v+u}=12kg-m/s

Given average speed=100Newtons  ⇒12/t (or) 0.12seconds.

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Thank you!

Answer 2

Answer:

Explanation:

A stone dropped from top of the tower touches the ground in 4 sec. the height of the tower is about is

Answer:

u=0,g=10 [taken g as 10] h=?

we can use the formula[ s= ut+1/2 at^2]

                                      [ h= ut+1/2 gt^2] take a=g s=h

                                       h=1/2gt^2

                                       h=1/210*4*4

                                       h=80m

Hope this answer is helpful