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## Homework Statement

A body of mass 50 g is dropped from a height of 20 m. A boy on the ground hits the ball vertically upwards with a bat with an average force of 200 N, so that it attains a vertical height of 45 m. The time for which the ball remains in contact with the bat is (g = 10 m/s^2)

## Homework Equations

F= ma

v^2 = u^2 + 2gh

h = -ut +1/2 at^2

## The Attempt at a Solution

v = √2gh = √2*10*20 = 20 m/s

This will become 'u' for the second part.

h = 45 m

a = F/m = 200 / 50 / 1000 = 4000 m/s^2

I substituted u, h & a in h = -ut + 1/2 at^2

I didn't get the answer which is 1/80th of a second.

I have tried using it by impulse method also.

Like, impulse = change in linear momentum = f * dt

mv - mu = f * dt

u = 20 m/s

I calculated v by v = √u^2+2gh = 10 √13

I still didn't get the answer.

I cannot understand where I am going wrong.

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