Booklet 5: Equilibrium, Moments and Torque

Question 1

Equilibrium

Answer 1

when an object has no resultant force acting on it, so is either at rest or constant velocity

Question 2

Moment of a Force

Answer 2

force x perpendicular distance of the pivot from the line of action of the force

Question 3

Principle of Moments

Answer 3

for any object in equilibrium, the sum of the clockwise moments about any point provided by the forces acting on the object equals the sum of the anti-clockwise moments about the same point

Question 4

Couple of Forces

Answer 4

equal and opposite, opposite directions, separated by a distance

Question 5

Torque of a Couple

Answer 5

one of the forces x perpendicular distance between the forces

Question 6

Archimedes’ Principle

Answer 6

the upthrust exerted on a body immersed in a fluid, whether partially or fully submerged, is equal to the weight of the fluid displaced by the body