Torque Switching and Directional Tension in Pulleys

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cjavier
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In the attached picture, one sees a pulley with a mass which is holding two different weights. In chegg, the tension due to a weight is represented as a downward direction. Then, when the tension is working on the pulley, the directions switch. WHY IS THIS?!

Thanks,
Cameron

pulley.png
 
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cjavier said:
In the attached picture, one sees a pulley with a mass which is holding two different weights. In chegg, the tension due to a weight is represented as a downward direction. Then, when the tension is working on the pulley, the directions switch. WHY IS THIS?!

Thanks,
Cameron

View attachment 56910
Tension forces always pull away from the objects on which they act. The cable tension force on the mass acts up. The cable tension force on the pulley acts down.
 
Tension and the force/load/weight always act opposite in direction. Think of tension as a load that balances the weight.
So when the tension is due to the mass m1 (which directs weight downwards) it is in the upper direction which will take a U-turn after the pulley.