Monday, 17 December 2012

Sunday, 16 December 2012


Forces give an object the energy to move, stop or change its direction.
Types of forces:
  1. Contact forces: There's a contact between two objects, two people or a person and an object.
  • To push: to move an object forwards.
  • To pull: to move an object backwards.
      2. Non-contact force: no contact takes place.
  •  Gravitya force that attracts an object to another.
         It is the force that pulls everything towards the Earth's surface.

  • Magnetism: It is the force the magnets produce.

Tuesday, 11 December 2012

Simple machines and complex machines.

Complex Machines.

 Complex machines are two or more simple machines working together.

e.g. A car is a complex machine; there are many simple and complex machines working together and at the same time.

Simple Machines

Simple Machines
A simple machine is a  device for altering a force.

Simple Machines: lever, bar, pulley, inclined plane, screw, wheel, axle and wedge.

1. Lever:: A lever moves on a fulcrum
      2.   Wheel:    A wheel spins around an axle.
3.   Pulley: A pulley is a wheel with a rope.
4. Inclined plane:
5. Wedge

6. Screw 

7. Axle