How to calculate force given Newtons, degrees, and friction

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Josef
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Homework Statement


A 400N trunk is on a 20 degree inclined plane and has a coefficient of kinetic friction of 0.56. What force must be exerted on the trunk to make it slide down the plane at a constant velocity?

Homework Equations

The Attempt at a Solution


I have drawn a free body diagram of the situation but am not able to derive an equation to calculate the force needed. Given an angle, I assume I will be using a trigonometric function.
 
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Josef said:
I have drawn a free body diagram
So what forces are there on the trunk and in what directions do they act?
 
The force of gravity acts upon it (downward direction), The normal force (parallel to the surface), and The force of friction in the opposite direction of the movement of the trunk.
 
Josef said:
The normal force (parallel to the surface)
Not parallel. It is called the normal force for a reason.
There is also the driving force to be found.

Next, you need to resolve all the forces into components. You can either choose the component directions to be vertical and horizontal or normal to the plane and parallel to the plane. Your choice.