state work energy theorem. derive it for constant force.

We know that according to the third equation of motion,

Multiplying both sides by m/2, we obtain

∴

Where,

= Final kinetic energy

= Initial kinetic energy

*W* = *FS* = Work done

Equation (i) is a special case of work energy (*WE*) theorem. The change in kinetic energy of a particle is equal to the work done on it by the net force.

**Work**

Work is said to be done when the point of application of the forces moves in the direction of the force.

If a constant force is applied on a body and the body has a displacement in the direction of the force as shown in fig, then the work done on the body by the force is given by,

When the displacement

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