Question

Define the friction force . name the various types of friction force .

Answer 1

Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. 
There are two main types of friction, staticfriction and kinetic friction. Static frictionoperates between two surfaces that aren't moving relative to each other, while kineticfriction acts between objects in motion...
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Answer 2

friction is the force  resisting the relative motion of solid surfaces, fluid layers and material  elements sliding against  each other. types of friction is dry friction force and etc.