Forces of motion, for year 5 students, A levels,,,

forces ppt

1. We don’t always see forces, but we can often see the result of a force. Forces cause objects to move or change their direction of movement. What Is Force? Force is a push or a pull . What actions can you think of that use forces?

2. There Are Two Types of Forces A contact force is between two objects that touch each other. Contact A non-contact force is between two objects that don’t touch each other. Non-Contact Some examples of contact forces are: air resistance, friction, spring, tension and buoyancy. Some examples of non-contact forces are: gravitational , magnetic and electric.

3. Also known as friction, this force involves two objects moving or rubbing against each other. This movement causes some resistance. Friction works against the motion of an object and acts in the opposite direction. Frictional Force Hand Shake Sanding Wood Brushing your teeth Walking

4. Air resistance is a type of frictional force that acts on an object as it moves through the air. Air Resistance Parachute Meteorite entering Earth’s atmosphere Windsock Tree in the wind

5. Spring force is applied to an object by a compressed or stretched spring that is attached to it. Spring Force Hand strengthener Car suspension Trampoline Keys on a keyboard

6. Tension force is a pull by a string or chain (or something similar) on an object. It is sometimes thought of as a stretching force. Tension Force Starting a lawn mower Pulling plants Playing with a pull toy Using a slingshot

7. Buoyancy force pushes objects upwards when they are in the water. Buoyancy Force A floating pool toy A Waka Hourua A life jacket Floating and sinking eggs

8. Gravitational force is when an object attracts another object towards itself. All objects have a gravitational force, but it is most noticeable in very large objects like the Earth or the Sun. The Earth pulls all objects towards itself due to its gravitational force. We can see the result of gravity but not gravity itself. Gravitational Force The tide coming in and out A ski jumper Pouring a drink A ball dropping

9. Magnetic force or magnetism is a force that acts on some metal objects. Iron, nickel and cobalt are examples of magnetic metals that can be affected by magnets. A magnetic field is an area around the magnet that ‘pulls’ the object. We can see the result of magnetism but not the magnetic force itself. It is invisible. Magnetic Force Magnets MRI, or Magnetic Resonance Imaging machine A directional compass Magnetic shoe laces

10. Electrical force occurs between two electrically charged objects. Objects can be negatively or positively charged. Appliances change electrical energy into other types of energy such as sound or light. Objects can be pushed or pulled by electrical forces. We can see the result of electricity but not electricity itself. It is invisible. Electric Force Lightning strikes An electric wheelchair Lighting Mobile phones