SIMPLE MACHINES

Machines help us to save time and energy. They make work easier.

Machines with no or few moving parts are called SIMPLE MACHINES.

Some examples:

A wheel is a solid disk that turns on an axle. We use wheels to move things from one place to another.

A pulley is a wheel with a rope around it. We use it to lift and lower objects.

A lever is a rigid bar. We use it to lift heavy objects. When we push down on one end of a lever, the other end goes up. Scissors and nutcrackers work with levers. 

An inclined plane is a ramp. We use it to move heavy objects up and down. 

COMPLEX MACHINES

Complex machines are made up of two or more simple machines working together.

They can also have these parts: motors, gears, electric circuits, electronic components…

Simple machines:
http://agrega2.red.es/repositorio/26012010/20/es-an_2009043062_7960422/index.html?ln18=en&pathODE=f12/2_ID/&maxScore=88&interfaz=interfaz_t01&titleODE=.:%20Simple%20machines.%20Types.%20:.   

The lever http://www.primaria.librosvivos.net/archivosCMS/3/3/16/usuarios/103294/9/The_lever_1/frame_prim.swf

Simple machines

http://www.edheads.org/activities/simple-machines/frame_loader.htm