Inclined Planes Aim How do forces acting on

Inclined Planes Aim: How do forces acting on an object change when it’s on a ramp?

Inclined Plane A tool used to move objects from one height to another without lifting directly against gravity

Inclined Plane FBD DO NOT DRAW THE COMPONENTS ON YOUR FBD FN Ff θ Fg θ

As the angle of the incline INCREASES… The Parallel Force INCREASES The Perpendicular Force DECREASES The object slides down at a QUICKER acceleration The Normal Force DECREASES as well The Friction Force DECREASES too

A 20 kg block is placed on a rough 30° ramp and remains at rest. (a) Determine the normal force and (b) force of friction FN Ff 30° Fg 30°

A 20 kg block is placed on a rough 30° ramp and remains at rest. (a) Determine the normal force and (b) force of friction FN Ff 30° Fg 30°

The 20 kg block is now placed on a frictionless 50° ramp and accelerates downward. (a) Calculate the normal force and (b) the acceleration of the block FN 50° Fg 50°

The 20 kg block is now placed on a frictionless 50° ramp and accelerates downward. (a) Calculate the normal force and (b) the acceleration of the block FN = 126. 1 N 50° Fg 50°

A 12 kg child slides down a 35° slide. Calculate the acceleration of the child if the coefficient of friction between the slide and his pants is 0. 25 FN Ff Fg 35°

A 12 kg child slides down a 35° slide. Calculate the acceleration of the child if the coefficient of friction between the slide and his pants is 0. 25 FN = 96. 43 N Fg = 117. 52 N Ff = 24. 11 N 35°

SUMMARY • Which direction does the… – Weight point? – Normal Force point? • Which “force” is equal to the normal force? – How do you calculate it? • Which “force” provides the natural inclination to slide down? – How do you calculate it? • If there is friction and the object is either stationary or sliding down at a constant speed, what relationship does the parallel force and friction have?