Assertion : Time taken by a body to complete a given work has nothing to do with energy of the body.
Reason : Because power of a body is the rate of doing work.

What do you mean by emissive power of a body?

The ability of a body to do some work is known as :

Power = Work xx Time taken to do the work.

Work done on the body by force or work done by the body ?

Assertion: The average speed of a body over a given interval of time is equal to the average velocity of the body in the same interval of time if a body moves in a straight line in one direction. Reason: Because in this case distance travelled by a body is equal to the displacement of the body.

In every day language, we often use the terms work, energy and power. The exact definition of these terms are related loosely to the physiological pictures these terms generate in our mind. Work done on a body is stored in the body in the form of energy. Thus, energy is capacity of the body to do the work. Power determines the rate of doing work. Tiem taken to complete the work is significant in power and not in energy. Read the above passage and answer the following questions : (i) Rakesh can put in long hours of work without getting tired. Does he have large energy or large power ? What is needed in boxing or karate ? (iii) Who is said to be a powerful leader ?

When a conservative force does positive work on a body, the potential energy of the body

Ability of a body to do work