What is friction?

 

               Friction is a type of force that stops things from moving when they have to slide past one another. It is the force that you have to overcome if you push something along. Friction also tends to slow down moving objects, which is why a bicycle will not travel very far if you stop pedalling. All forms of moving machinery are subject to friction. Oil is used to reduce the level of friction and this helps to make machines work more efficiently.

 

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