(a) Explain with the aid of a diagram what is meant by the moment of a force about a point. (b) State the conditions of equilibrium for a number of coplanar...

Question 1 Report

(a) Explain with the aid of a diagram what is meant by the moment of a force about a point.

(b) State the conditions of equilibrium for a number of coplanar parallel forces. 

A metre rule is found to balance at the 48cm mark. When a body of mass 60g is suspended at the 6cm mark, the balance point is found to be at the 30cm mark. Calculate:

(i) the mass of the metre rule; (ii) the distance of the balance point from the zero end, if the body were moved to the 13cm mark.

(c) Show that the efficiency E, the force ratio M.A and the velocity ratio V.R of a machine are related by the equation \(E = \frac{M.A}{V.R} \times 100%\)

The efficiency of a machine is 80%. Determine the work done by a person using this machine to raise a load of 200kg through a vertical distance of 3.0m.

[Take g = 10ms\(^{-2}\)]