1. 6.3 Force melon seed Nature of force A force can ucause an acceleration on an object. uproduce noticeable effects on an object. a change in speed e.g. it breaks or changes the shape of an object. or direction

2. 6.3 Force produces an acceleration of 1 m s -2 on a mass of 1 kg. uForce is measured in newton (N). A force of 1 N Frictionless surface 1 kg wooden block a = 1 m s -2 1 N

3. 6.3 Force uForce has both uA force can be represented by an arrow: length of the line F arrow head magnitude of force direction of force magnitude and direction. Force is vector quantity. 

4. 6.3 Force uObjects in contact may exert forces on each other: When a string is pulled, the forces exerted by the string is known as tension.

5. 6.3 Force u Objects not in contact may also exert force on each other. Two magnets with like pole repulse each other. The Earth exerts an attractive gravitational force on the falling tennis ball. weight

6. 6.3 Force Addition of forces  Forces acting on an object can be added using: l Tip-to tail method l the parallelogram of forces

7. 6.3 Force Tip-to-tail method F2F2 F1F1 components of F F Resultant force

8. 6.3 Force F2F2 F1F1 The parallelogram of forces F Resultant force diagonal

9. 6.3 Force The resultant force acting on an object = 0 resultant force = weight – supporting force = 0 The object is in equilibrium. weight W supporting force R Consider a man standing on the ground…

10. 6.3 Force Algebraical method for addition of forces By using Pythagoras’ Theorem, F F2F2 F1F1 x y  EXTENSION magnitude of F: direction of F: Consider the forces F 1 and F 2 below:

11. 6.3 Force F x y  F x : component of the force F along the x-axis F y : component of the force F along the y-axis Resolution of forces A force F can be resolved into two perpendicular components: F x and F y FyFy FxFx

12. 6.3 Force Algebraical method for resolution of forces F x = F cos  F y = F sin  EXTENSION F x y  FyFy FxFx

13. 6.3 Force That’s the end of Section 6.3 Check Point Key Ideas Previous Page Exit