This document discusses concepts related to moments, including the definition of moment of force as force multiplied by perpendicular distance (Fd), that anticlockwise moments are positive, and that for a rigid body in equilibrium the total moment about any point must equal zero. It also notes that when a rod rests on two supports and pivots about one, the reaction at the other support will be zero.

1. BY
T O’Brien

2. MOMENTS

3. F
Moment of F about O = Fd
d
O
Anticlockwise moments are
taken as positive
Units = Nm
If a rigid body is in
equilibrium the resultant
force is 0 and the total
moment about any point is 0.
When a rod resting on two
A D supports is about a pivot
about one of the supports,
B C the reaction at the other
support is 0.

4. CENTRE OF MASS

6. VARIABLE ACCELERATION

8. UNIFORM CIRCULAR MOTION

10. WORK, ENERGY AND POWER

12. HOOKE’S LAW