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High School 

[Physics] WEBASSIGN - Friction + Application

WARNING: Lots of images.
Between my friend and myself, we've tried all of these and are beyond stumped. Any help (equations, answers, videos, anything) would be greatly appreciated. These are due tonight, unfortunately.
"Friction"Spoiler (Click to View)
I'll go over question 2 and hopefully you can apply that to all of them. Static friction is used if it's still and kinetic is for if it's moving. Start with static, if you see that it's moving, switch to kinetic.

2. downwards force = gravitational force + push force = m*g + F*sin(25) = 36*9.8 + F*.422
force to the right = F*cos(25) = .91*F
Force to the left = static friction * force going downwards = .1*(36*9.8 + F*.422) = 35.28+F*.0422

Force required to make it move would be force to the right > force to the left. So
.91*F > 35.28 + F*.0422
(.91-.0422)F > 35.28
.8678F>35.28
F>40.65 Newtons.

Part b.
Now that it's moving we use the kinetic friction, and it's clarified we're using the same force. So
Force to the right = .91*40.65
Force to the left = .03*(352.8+40.65)
Net force = .91*40.65 - .03*(352.8 + 40.65) = 25.188 = m*a
a = 25.188/m = 25.188/36 = .7m/s^2


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