(Non/)Equlibrium and Newton's Laws of Motion

AI Thread Summary
The discussion revolves around calculating the acceleration of a crate sliding down a ramp inclined at 33.6° with a coefficient of kinetic friction of 0.485. Participants clarify that while mass is not specified, it can be treated as a variable 'm' in the equations. The net force equation is established as mgsin(θ) - μmgcos(θ) = ma, which simplifies to gsin(θ) - μgcos(θ) = a when divided by mass. This approach confirms that mass cancels out, allowing for the calculation of acceleration without needing its specific value. The conversation emphasizes understanding the underlying principles of motion and friction in this context.
Gannon
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This is mainly stumping me because of the absence of any force or mass.

Homework Statement



A crate is sliding down a ramp that is inclined at an angle of 33.6° above the horizontal. The coefficient of kinetic friction between the crate and the ramp surface is 0.485. Find the acceleration of the moving crate.

\mu_{k}= .425
\theta = 33.6
g = 9.8m/s^{2}

Homework Equations



Well, F_{net}x = ma , but there is no mass... I don't know where to go from here. :frown:

Any help is appreciated. Thanks.
 
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If you think about the ideal concepts of this type of motion, you can see that mass does not matter. Start to solve the equation as if you had a mass (just use 'm' in place of the unknown quantity) and you'll see it's not as important as you think. If you get stuck in the actual solving, post again with your progress.

Bryan
 
Ok... I think I'm on the right track. So the net force will be simply

mgsin\theta - \mumgcos\theta = ma

You can divide everything by mass, leaving

gsin\theta - \mugcos\theta = a.

Is this correct?
 

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