In vector form, work done W is written as:

1. $\vec{W} = \vec{F}.\vec{S}$
2. ${W} = \vec{F}.\vec{S}$
3. ${W} = \vec{F}$x $\vec{S}$cos θ
4. $\vec{W}$= F x S cos θ

For work done to be maximum, the angle between the force and displacement should be :

1. 0°
2. 30°
3. 45°
4. 90°

When a ball m is thrown upwards to a height h, the work done by the force of gravity is:

1. mgh
2. -mgh
3. mg
4. mgh²

The S.I. unit of work is:

1. Joule
2. erg
3. Newton
4. dyne