The document discusses force, pressure, and friction. It defines force as a push or pull and explains that forces can change the speed, direction, or shape of an object. It also distinguishes between elastic and inelastic objects based on whether they return to their original shape after a force is applied. Friction is described as a force that opposes motion.

2. RELATIONSHIP BETWEEN FORCE AND PRESSURE FRICTION EFFECTS OF FORCE INTRODUCTION FORCE

3. - playing a guitar - scrubbing the floor - sawing wood - rowing a boat A pull is when we apply a force to move an object towards our body A force to move an object away from our bodies FORCE A force is a push or a pull or both. A force cannot be seen but we can feel and observe the effects of the force. PUSH PULL COMBINATION OF PUSH AND PULL

4. Pressing the switch Kicking a ball Launching rocket Pushing trolley Knocking a nail

5. Tug-of-war Raising a flag Pulling a box Opening the door Drawing back a bow

6. Rowing a boat Scrubbing the floor Sawing wood Playing guitar

7. Stops a moving object or makes a stationary object moves Change the speed of a moving object Change the direction of a moving object Changes the shape permanently Changes the shape temporarily EFFECTS OF A FORCE

8. Stretch a rubber band After An object that will return to its original shape and size after being squeezed, pressed, twisted and stretched is elastic After After Press a sponge Squeeze a spring

9. Drop a glass After After Tear a piece of paper After Crush an empty can An object that will not return to its original shape and size after being squeezed, pressed, twisted and stretched is inelastic

10. A solid cannot be compressed or stretched!! IMPORTANT POINT EXPLANATION The shape of a solid object changes when a force is applied to it whether it’s temporarily or permanently Example: crushing a can – changes the shape permanently

11. when a force is applied in the opposite direction (or different direction), the moving object will change its moving direction

12. Misconception? A force is needed to keep an object moving with a constant speed Explanation: You do not need forces to move at a steady speed but if you keep the same speed yet change direction, like a moon around a planet, then you have a force acting on you anyway An object will move faster when a force is applied It moves in the same direction as the applied force

13. A stationary ball will move when it is kicked Moves in the same direction as the applied force The moving ball will stop when an equal force is applied in the opposite direction of its motion

14. Force is a property of an object. An object has force and when it runs out of force it stops moving EXPLANATION an object at rest or in motion will remain in that state unless an external force is applied to the object Newton 1 st Law