Question

PHYSICS - KINEMATICS

Answer 1

Hope u like my process
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Ceasing of Acceleration means Acceleration will be 0.

This happens only velocity is constant

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So after half distance velocity will be same as when it hit the ground.
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Formula to be used
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=> v² = u² +2gh

Where v = final velocity, u= initial velocity, g = gravity, h= height.
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Since ball is dropped,

=> u =0 m/s

=> g =10 m/s

=> h = 40/2 = 20 m

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$= > {v}^{2} = {u}^{2} + 2gh \\ \\ = > v = \sqrt{ {0}^{2} + 2 \times 10 \times 20} \\ \\ = > \bf \: v = \underline {20 \: \: m {s}^{ - 1} }$
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So,
The required velocity =20 m/s
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Hope this is ur required answer

Proud to help you

Answer 2

Answer:

Kinematics is a subfield of classical mechanics that describes the motion of points, bodies, and systems of bodies without considering the forces that cause them to move. Kinematics, as a field of study, is often referred to as the "geometry of motion" and is occasionally seen as a branch of mathematics.