PHY 2020 Chapter Notes - Chapter 4: Friction, The Crate, Net Force
Document Summary
Force: any push or pull exerted on an object, measured in (cid:374)e(cid:449)to(cid:374)"s. Most often, he applied force is not the only force acting on an object. Acceleration depends on net force: to increase acceleration of an object, you must increase the net force acting on it. Checkpoint 1: (1) you push on a crate that sits on a smooth floor, and it accelerates. Friction: the resistive force that opposes the motion or attempted motion of an object either past another object with which it is in contact or through a fluid. When you apply a force to an object, friction usually reduces the net force and the resulting acceleration. Friction is caused by the irregularities in the surfaces in mutual contact, and it depends on the kinds of material and how much they are pressed together. The direction of the friction force is always in the direction that opposes motion. Static friction is somewhat greater than sliding friction.