In figure below, a uniform bar of length l m is supported at its ends and loaded by a weight W kgf at its middle. In equilibrium, find the reactions R1 and R2 at the ends.

The centre of gravity of a body is the point about which the algebraic sum of moments of weights of all the particles constituting the body is:

1. 1
2. > 1
3. < 1
4. 0

Where should the centre of gravity of a body be located for stable equilibrium?

1. above the base
2. near the geometric centre
3. can be anywhere
4. both (1) and (2)

Two objects have the same mass but different shapes. Which object would have a higher centre of gravity?

1. the one with a larger base
2. the one with a smaller base
3. both would have the same centre of gravity
4. it depends on the material of the object.