(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A box of textbooks of mass 24.0 Kg rests on a loading ramp that makes an angle θ with the horizontal. The coefficient of kinetic friction is 0.25 and the coefficient of static friction is 0.36.

a)As the angle is increased, find the minimum angle at which the box starts to slip

b)At this angle, find the acceleration once the box has begun to move

c)At this angle, how fast will the box be moving after it has slid a distance 4.8 m along the loading ramp?

2. Relevant equations

f=un

n=mgcosθ

3. The attempt at a solution

a)f_{s}=u_{s}n=ma=0

u_{s}mgcosθ=0

θ=cos^{-1}(-umg)

θ=cos^{-1}(-0.36*24*9.8)

θ=cos^-1(-84.67)

This is pretty much the only question I'm having trouble with, b and c I can figure out once I find θ. As always any help is much appreciated.

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# Homework Help: Force of Friction and θ

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