- #1
Tyler_Cavan
- 8
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Homework Statement
A box of textbooks of mass 25.0 kg rests on a loading ramp that makes an angle "a" with the horizontal. The coefficient of kinetic friction (muk) is 0.230 and the coefficient of static friction (mus) is 0.340.
a) As the angle "a" 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 5.30 along the loading ramp?
2. Homework Equations /Attempts
I have solved a), with an answer of 19 degrees, and my answer for b) does not seem to be right although I can't see where I went wrong. I cannot complete c) till b) is finished.
for b):
F= ma
mgsin"a" - (muk)mgsincos"a" = ma
therefore:
a = g*sin"a" - (muk)*g*cos"a"
and I get a = 1.059 which is wrong.
Any insight is appreciated.