1. Loads & Forces

2. L1 L2 F2 F1 F1 x L1 = F2 x L2 F1 = (L2 x F2) L1 Formula for calculating load

3. Exercise L1 = 1.5m L2 = 25cm F2 = 100kg F1 = ? L1 = 2.0m L2 = 20cm F2 = 500kg F1 = ? L1 L2 F2 L1 L2 F2

4. Exercise L1 L2 F2 L1 = 3.0m L2 = ? F2 = 100kg F1 = 30Kg L1 L2 F2 L1 = ? L2 = 10cm F2 = 500kg F1 = 50kg

5. Equilibrium 10kg Fulcrum (pivot point) Force 1 Force 2 The above diagram shows two loads / weights equidistant from each other supported by a fulcrum. Because the forces and distances are equal the system is in equilibrium.

6. Centre of Gravity The above illustration shows a hammer placed on a fulcrum. What do you think will happen? Why do you think this happens? The hammer balances because the weight of the head multiplied by the distance from the fulcrum is equal to the weight of the handle multiplied by the distance from the fulcrum.

7. Newton’s Laws Newton’s first law states; –Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it. Newton’s second law states; –The relationship between an object's mass m, its acceleration a, and the applied force F is F = ma. Acceleration and force are vectors (as indicated by their symbols being displayed in slant bold font); in this law the direction of the force vector is the same as the direction of the acceleration vector. Newton’s third law states; –For every action there is an equal and opposite reaction.

8. Newton’s Third Law Mass of cannon ball X acceleration of cannon ball Mass of cannon X acceleration of cannon

9. Newton’s third law If the force of the push is 9kg what happens? The force applied by the weight excluding friction is 10kg

10. Moments of Force Moment = Force x Perpendicular Distance M = F x d (Nm) = (N) x (m) The load required to move / rotate a force around a fixed point is known as a moment of force. Simple moment calculations are described below. More complicated calculations are required when there is more than one force pulling in different vectors.