Forces problemfind effective weight of mass (3 masses)

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SUMMARY

The discussion centers on calculating the effective weight of mass m3 (10 kg) in an elevator scenario involving three masses (m1=500 kg, m2=1500 kg) and a force (f1=600 N) at a 25-degree angle. The effective weight is defined as the apparent weight experienced by an object in a non-inertial frame, such as an accelerating elevator. The coefficient of kinetic friction is given as 0.25, which influences the forces acting on m2. Participants suggest using trigonometric functions to resolve f1 and emphasize the importance of drawing free body diagrams (FBD) to visualize forces.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Knowledge of free body diagrams (FBD)
  • Familiarity with trigonometric functions in physics
  • Concept of effective weight in non-inertial frames
NEXT STEPS
  • Study the concept of effective weight in accelerating frames of reference
  • Learn how to construct and analyze free body diagrams (FBD)
  • Explore the application of trigonometric functions in force resolution
  • Investigate the effects of friction on motion in elevators
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Students studying physics, particularly those focusing on mechanics and forces in non-inertial frames, as well as educators seeking to clarify concepts related to effective weight and free body diagrams.

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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?
 

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