Some guidance please Newton's Laws

AI Thread Summary
The discussion revolves around calculating the coefficient of kinetic friction and the acceleration of a crate being pushed and pulled at an angle. The coefficient of kinetic friction was determined to be 0.26 when the crate is pushed with a force of 300N at a 20-degree angle below the horizontal. For the pulling scenario, participants suggest using a free-body diagram and the equation of motion in the horizontal direction to find acceleration. The user attempted to calculate acceleration using the formula F = m*a but faced confusion regarding the correct application of forces and the coefficient of friction. Overall, the user is seeking clarity on how to properly incorporate these elements to solve for acceleration.
jlshoop
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A1000N crate is being pushed across a level floor at a constant speed by a force of 300N at an angle of 20 degrees below the horizontal.
(a) what is the coefficient of kinetic friction between the crate and the floor

I was able to find this which is = .26

(b) If the 300N force is instead pulling the block at an angle of 20 degrees above the horizontal what will the acceleration of the crate be?(assume that the coefficient of friction is the same as found in (a))

Help I need guidance on this part!
 
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Have you tried working this out yourself? Draw a freebody diagram and write the equation of motion in the horizontal direction, solve for a.
 
I was afraid it would seem that way if i didn't describe all my attempts to solve it.

I am confused, my best bet was to use the equation
F= m*a
because i know that I could find my acceleration from this formula
So I applied it using the numbers from the problem
m=w/9.8
m=897/9.8 = 91.53
F=282

282/91.53 = a = 3.1

which is not right
plus i didn't use the coefficient

So i thought, if i apply
F=μN
F=.26 * 897 = 233

then
233/91.53= 2.54
also not right

so I'm lost.
 
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