Forces and Friction

A force is simply a push or a pull. There are lots of different forces you need to know about:

• Gravity or weight always acting straight downwards
• Reaction force from a surface, usually acting straight upwards
• Electrostatic force between two charged objects. The direction depends on the type of charge (like charges repel, opposite charges attract)
• Thrust or push or pull due to an engine or rocket speeding something up
• Drag or air resistance or friction which is slowing the thing down.
• Lift due to an aeroplane wing.
• Tension in a rope or cable.

Friction is alwsys there to slow things down

• If an object has no force…