Finding Frictional Coefficient for Constant Speed Crate

[Booska]

Homework Statement

1000N crate pushed at constant speed 300N at angle 20* below horizontal. I need to find the frictional coefficient.

Homework Equations

The Attempt at a Solution

I don't think I am even diagramming this right but here goes, Downward force is (1000N)(9.8m/s^2) Upward is (300N)(Sin20*), To the right is (300N)(cos20*) an I have no idea about to the left... I was sick in class and am pretty behind now trying to play catchup but none of the examples in the book are quite like this and I can't find very relevant help elsewhere online. Plz help=]

 

[PhanthomJay]

Is there a sketch that goes along with this problem? You first have to be sure of the direction of the 300 N applied force that acts at 20 degrees below the horizontal. Is this force pushing down and to the right or up and to the right? I interpret it as acting downward and to the right, in which case it has a downward component, not an upward one. After you resolve this dilemma, you need to draw a free body diagram and show all forces acting on the crate, in both the x and y directions. There are several. Then you need to apply Newton's laws in the x and y directions. You will probably need to 'catch up' with what you missed in class by talking directly to your instructor, assuming your instructor is human and not a machine.