# A machine is an instrument that multiplies force

• Slides: 16

�A machine is an instrument that multiplies force to make work faster and easier. We can classify machines into two groups, depending on faster complexity: Simple machines and complex machines.

� Simple machines have usually got one or two parts. The inclined plane, the pulley and the levers are simple machines.

� Ramps are inclined panes that we us to go up and down. We can also use inclined planes to move heavy loads more easily. � This is a ramp of a burgonet.

�A pulley is a wheel with an axle in the centre and a rope that runs around the outside. We use a pulley to change the direction of a force that we are applying.

�A lever consists of a rigid bar called the fulcrum. There are three elements: The effort. The resistance. The fulcrum. This is an example of at the levers.

� Effort is the force placed on the simple machine to move the load. Also called applied force or input force. The effort.

� The resistance is the force which an effort force must overcome in order to do work on an object a simple machines. Resistance force, like most other forces, is measured in newtongs or in pounds-force. The resistance.

� There is a rigid bar that turns on a fixed point. The fulcrum.

� The lever is a simple machine consisting of a rigid bar that is free to pivot on a fulcrum. � Depending on the position of the force (F), the load or resistance (R) and the fulcrum, there are : Class 1 lever. Class 2 lever. Class 3 lever.

� What is a machine? � A machine is an instrument that multiplies force to make work faster and easier. � Simple machines have usally got… � One or two parts. � One example of inclined planes. � Ramps.

� What is a pulley? � A pulley is a wheel with an axel n the centre and a rope that runs around the outside. � What are the parts of the levers? � The parts of the levers are the effort, the resistance and the fulcrum. � How many class of levers there are? � There are 3 class.

� What are there? � There are class 1 lever, class 2 lever, class 3 lever. � What is the effort? � The effort is the force placed on simples machines. � What is the resistance? � The resistance is the force which an effort force.

� What is the fulcrum? � The fulcrum is a rigid bar that turns on a fixed point.

By: Lucia Haba Niso. Course: 5ºA. School: C. P. Pio Baroja.