Forces problemfind effective weight of mass (3 masses)

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Homework Statement


http://i50.tinypic.com/r8gfba.png

^That is the image I got in class

m1=500kg
m2=1500kg
m3=10kg
f1=600n
angle near f1=25 degrees
coefficient of kinetic friction=.25

Find effective weight of m3 in side of elevator
Find force required to keep the elevator at constant velocity

Homework Equations


All I know is Ft=ft for both
I have a feeling f1 is either sin25(600) or cos25(600)..I don't know what 'effective weight' really means


The Attempt at a Solution



Would m1 just be 9.81(500) since it's going straight up and down..does Fn=Fg here?

For the second part, I know I probably have to set a to zero, but I can't do that when I don't know where to start
 
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Effective weight is the apparent weight of the object. Imagine you're standing in the elevator and it's moving up very fast. You are going feel heavier than if the elevator was not moving. If the elevator is moving down you will feel lighter.

Draw your fdb and then find acceleration.
 
I don't understand why the angle next to F1 is there, or why there is even an F1. What is it exactly? I can't attempt to find the overall force when I don't know what to do with that.

so, I think f1=253.6 N

For M2, is it (.25)(sin25)(1500)=ma

m1 is (9.81)(-500)=ma

and I combine? or do I add F1 to M2 first..or am I completely wrong?