The direction of rotation of a pivoted body can be changed by changing:

1. the direction of force
2. the point of application of force
3. both the direction of force and the point of application of force
4. the magnitude of force

A couple is formed when …………… are not acting along the same line

1. two unequal and parallel forces
2. two equal and parallel forces
3. two equal and opposite parallel forces
4. two unequal and opposite parallel forces

A body is acted upon by two unequal forces in opposite directions, but not in the same line. The effect is that:

1. the body will only have rotational motion
2. the body will only have translational motion
3. the body will have neither rotational motion nor translational motion
4. the body will have rotational as well as translational motion.

Out of the following which one is an example of dynamic equilibrium ?

(1) Moon revolving around the earth
(2) A pebble fixed at the end of a string whirling in a circular path
(3) An aeroplane moving at a constant height
(4) A beam balance balanced in a horizontal position.

1. (3) and (4)
2. (1), (2) and (3)
3. (1) and (2)
4. (1) and (3)