Dragging an object: what is Fmin and magnitude of acceleration?

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AI Thread Summary
The discussion focuses on the challenges of setting up a physics problem involving the dragging of an object, specifically regarding the equations needed to determine the normal force and acceleration. The user expresses confusion over using trigonometric functions and the correct application of forces, including the weight of the object and its components. A key point made is that the normal force is not simply the weight of the object, as the pulling force affects it. The suggestion to create a free body diagram is emphasized as a helpful step in visualizing the problem. Ultimately, the user successfully solves the problem after seeking guidance.
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Homework Statement
By pulling a on rope attached to a crate of mass 124.0 kg, the crate is dragged across a floor. Let the coefficient of static friction between the crate and the floor be 0.860 and the angle between the rope and horizontal is 39.6 °. Find the minimum force required to move the crate.
At a later time the crate is now dragged with this same force, and has already started moving, on a wet floor where the kinetic friction coefficient is 0.516. What is the magnitude of the acceleration of the crate?
Relevant Equations
Fn = m*a or m*g (I think this is necessary)
I am not sure how to set this problem up mainly, I am unsure of what equations I need to be using right now. I have tried, for some dumb reason, a multitude of combinations with Cos(39.6) and 124 kg*9.8 m/s^2 as well as one time multiplying the coefficient. I am mainly just struggling with what equations I am meant to be using and believe me I have tried google and I just feel really stupid when I look at this problem so I don't know who else to ask as I feel bad milking my classmates for help with these problem set-ups.

I know that:

124*9.8 (m*g) = 1215.2 N
Cos (39.6) = 0.771 (rounded)
Sin (39.6) = 0.637 (rounded)

So I assume that Normal Force is the 1215.2 N right?

I also know that there's the applied force formula with x-component and y-component (Fa = Fax i + Fay j) would that be necessary for this problem?

I am going to set up a tutor for myself at my school to try and get more into the swing of knowing when to use what equations, there are just so many that I am a bit lost.
 
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I suggest starting with a nice free body diagram
 
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tomiharv said:
So I assume that Normal Force is the 1215.2 N right?
Wrong. ##mg=1215.2~##N is the weight of the crate. The pulling force has a vertical component away from the floor that lessens the burden of the full weight on the floor.

Follow @Gordianus's hint and draw a nice free body diagram. Then you will be able to see how this is put together.
 
GUYS UPDATE I DID IT I SOLVED IT
 

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