Forces are essentially pushes or pulls.  These can be exerted in a variety of different ways.  Some typical forces include gravity, friction, and magnetic forces.  Forces are measured in Newtons, (N)

Gravity

Every object with a mass is pulled down to Earth by the force of gravity.  we call this pull the weight of an object.  As a result THE ONLY UNIT OF WEIGHT IS THE NEWTON.

Friction

Friction is the movement of an object. This can be two surfaces rubbing together or the force required to move the object through a fluid such as water or air. Friction is a dynamic force. That is to say it is constantly changing depending upon the speed of the object and the substance it is moving over or through. These other videos on friction may also be of use.

Air resistance

Air resistance is a form of friction.  This video helps to explain what air resistance is. If you don’t like watching eggs fall from a great height this one is not for you.

Terminal velocity

This is a little advanced but the video is a nice one. If you enjoy sky diving you’ll like it.

Magnetic

Magnetic forces can either be pushes or pulls. Magnets can either be permanent magnets or electromagnets which use electricity to generate a magnetic field.

Electromagnets can be turned on or off.  Electromagnets can be used to pull things closed such as gates or locks or they can be used to push things such as a maglev train

Buoyancy and upthrust

Buoyancy and upthrust follow Archimedes’ principle.  these videos here should help explain this.  They also explain density well

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