Question

State and prove work energy theorem. Find the value of kinetic energy of a body of mass 25 Kg after 10s which accelerates uniformly from rest.​

Answer 1

Answer:

Here is your answer .

Explanation:

Work energy theorem states that the change in kinetic energy of an object. is equal to the ... Let us suppose that a body is initially at rest and a force. F. is applied ... Then, a small amount of work done is given by ... where a is acceleration produced (in the direction of force) on applying the force.

Answer 2

Explanation:

Work energy theorem states that the change in kinetic energy of an object

is equal to the net-work done on it by the net force.

Let us suppose that a body is initially at rest and a force.

F

is applied on the body to displace it through

d

s

along the direction of the force. Then, a small amount of work done is given by

dw =

F

.d

s

= Fds

Also, according to Newton's second law of motion, we have

F = ma

where a is acceleration produced (in the direction of force) on applying the force. Therefore,

dw = Mada = M

dt

dv

ds

Now, work done by the force in order to increase its velocity from u (initial velocity) to v (final velocity) is given by

W = ∫

u

v

Mvdv = M∫

u

v

vdv

= M∣

2

v

2

∣

u

v

W =

2

1

Mv

2

−

2

1

Mu

2

Hence, work done on a body by a force is equal to the change in its kinetic energy.