PHYS 1P22 Lecture Notes - Friction, Rolling Resistance, Spring Scale
Document Summary
There are four types of friction namely: static friction, kinetic friction, rolling friction, fluid friction. Definition: friction is a force that opposes relative motion between two surfaces in contact. A force of friction acts: when solid surfaces slide, or try to slide, across each other, when an object moves through air (/gas) or water (/liquid). The kinetic energy of the moving object is converted to heat energy by the force of friction. Friction can be a help or a hindrance. We could not walk if it did not exist between the soles of our shoes and the ground. Our feet would slip backwards; as they tend to if we walk on ice. On the other hand, engineers try to reduce friction in moving parts of machinery by using lubricating oils and ball-bearings. When a gradually increasing force p is applied through a spring balance to a block on a table, it does not move at first.
