# Q.A number of forces acting at a point will be in equilibrium, if

• AAll the forces are equally inclined
• BSum of all the forces is zero
• CSum of resolved parts in the vertical direction is zero (i.e. ∑V = 0)
• DNone of these

Sum of resolved parts in the vertical direction is zero (i.e. ∑V = 0)

Hints :

The coefficient of friction depends upon

The efficiency of a lifting machine is the ratio of