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jmm5180
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Homework Statement
How much work is done by friction when a box with an apparent mass of 325kg moves horizontally across a floor with coefficient of friction of .33 and is pulled at 59.9 degree angle for 2.60 m? What is the force that is pulling the box?
Homework Equations
W=Fdcos@ (@= theta)
Fnet=ma
The Attempt at a Solution
I searched for what apparent mass was, but what I found seemed to do with volume and water displacement, which aren't related to this problem. Instead I tried solving the second question first because I needed Normal force to solve the work done by friction.
For my free body diagram, I had force applied (Fa) in the y direction upwards on the y-axis along with normal force. Along the negative y-axis I had weight. Force of friction (Ff) was along the negative x axis, and force applied in the x direction was on the positive x axis.
In the x direction...
Ff=Facos@ (since no acceleration)
uN = FaCos@
In the y direction...
Fasin@ + N = W (again since no acceleration)
N= mg - FaSin@
So plugging in,,,
u(mg-Fasin@) = FaCos@
Solving for Fa I got...
umg-uFasin@ = Facos@
Fa= umg/(usin@ + cos@)
Fa= (.33*325 kg*9.8)/(.33sin59.9+cos59.9)
Getting that the force applied = 1335.50 N, but this is not correct.
Any help would be appreciated, thanks in advance.