Work , Energy & Power

The concepts of Work and Energy can be applied to all MCQs, dealing with momentum , force , velocity , acceleration and height.

Work Energy Theorem
Work Energy Theorem states that the amount of Work Done is the change in Kinetic Energy.

Nature of Work
Work is a scalar product which occurs in the direction of Force applied.

Conservative Forces
The forces that conserve kinetic energy are called as conservative forces.

Kinetic Energy
Kinetic Energy is the energy of a body by virtue of its motion.

Potential Energy
Potential Energy is the energy of a body by virtue of its shape, size , position. A body always tries to move to the position of lowest potential energy.

Mass - Energy Equivalence
E = mc2

Co-efficient of restitution
e = [u1- u2] / [v2 - v1]

For an object bouncing back from height h and and stopping after covering d horizontal distance can be given by the series :-

d = h + 2h(e2+e4+e6+.......)

The velocity of an object after collision is e times that of velocity before collision.

Power
Power is the rate of doing Work.