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seiferseph
Jun13-05, 06:01 PM
http://i2.photobucket.com/albums/y15/seiferseph/untitled.jpg

recently had this question on a test, we're told the left block moves up the incline at a constant rate. heres what i did

Fnet = Fappl - Fopp
Fnet = 0 because no acceleration

Fopp = Fappl

the applied force would only be the weight of the right one, and the opposing force would only be friction on the incline?
does the force weight of A (Fw for a times sin theta) also oppose the motion?
whozum
Jun13-05, 06:03 PM
The net force on WHAT is zero? Do a force diagram for each block. The one on the right has a force of gravity pulling down and a force of tension pulling up, however it is sitll descending, which tells you something.
seiferseph
Jun13-05, 06:05 PM
The net force on WHAT is zero? Do a force diagram for each block. The one on the right has a force of gravity pulling down and a force of tension pulling up, however it is sitll descending, which tells you something.

that is taking the system, since there is no accel the fnet if the system is zero, and the applied force is the weight of the hanging one. i was wondering what the opposing forces would be.
whozum
Jun13-05, 06:40 PM
The right block (descending) has an et force of zero, which means the force of gravity pulling down equals the force of tension, pulling up. What's causing the force of tension? The other block, so whats the force on the other block...
seiferseph
Jun13-05, 06:54 PM
just got it, thanks!