Another pulley problem (answer check)

AI Thread Summary
The discussion revolves around a pulley problem in physics, focusing on the relationship between forces and mass. It highlights the confusion regarding the normal force, which is described as mgcos(theta), and the dimensional inconsistency in the selected answer options. Participants emphasize that mass cannot be compared directly to force without proper conversion. The resolution involves recognizing that the gravitational constant (g) needs to be adjusted to align the units correctly. Ultimately, the correct approach clarifies the necessary adjustments to solve the problem accurately.
Lori

Homework Statement


upload_2017-11-8_14-29-34.png


Homework Equations


Shown above

The Attempt at a Solution



Shown above.

Since the normal force is just the force opposite to the surface (gravity force) , it's just mgcos(theta).
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The option you selected has mass (m) on the left but forces (mg) on the right.
 
haruspex said:
The option you selected has mass (m) on the left but forces (mg) on the right.
isnt the answer just the left horizontal forces? so friction + horizontal component force from gravity
 
Lori said:
isnt the answer just the left horizontal forces? so friction + horizontal component force from gravity
Please try to understand what I wrote. The option you selected makes no sense dimensionally. It does not mean anything to say that a mass is more or less than a force.
 
haruspex said:
Please try to understand what I wrote. The option you selected makes no sense dimensionally. It does not mean anything to say that a mass is more or less than a force.
Ohhh. I just need to remove the g by dividing to get it in mass . So option a
 
Lori said:
Ohhh. I just need to remove the g by dividing to get it in mass . So option a
Right.
 

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