Question

Define Kinetic Energy and derive the expression for the same . Give its SI unit

Answer 1

The energy possesed by a body when in motion is called its Kinetic energy.

Using equation of motion

2aS = Vf^2 – Vi^2 
Putting the above mentioned values 
2ad = V^2 – 0
a = V^2/2d

Now force is given by
F = ma 
Putting the value of acceleration
F = m(V^2/2d) 
As we know that 
Work done = Fd

Putting the value of F
Work done = (mv^2/2d)(d)
Work done = mV^2/2
OR 
Work done = ½ mV2

Since the work done is motion is called "Kinetic Energy"

KE=1/2mv^2

Its SI Unit is Joules (J)

Answer 2

Answer:

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