Explain the following:

It is advantageous to run before taking a long jump.

The force needed to stop a moving body in a definite time depends on:

1. mass of the body
2. velocity of the body
3. both (a) and (b)
4. none of these

Newton's first law of motion defines force :

1. quantitatively
2. qualitatively
3. both (a) and (b)
4. none of these

According to Newton's second law, the acceleration produced in a body is:

1. inversely proportional to the force applied on it
2. directly proportional to the force applied on it
3. not dependent on force
4. none of these