Is this a mistake on the answer key? (Newton's Laws)

AI Thread Summary
The discussion revolves around the confusion regarding the angle measurement in a physics problem related to Newton's Laws. Participants clarify that the angle is measured from the y-axis, making it 60 degrees, while the angle to the x-axis is indeed 30 degrees. They explain that the vertical and horizontal components of the force can be expressed using both angle measurements, confirming their equivalence. The conversation highlights the importance of understanding angle references in physics problems. Overall, the exchange contributes to better comprehension of the problem for exam preparation.
Lori

Homework Statement



upload_2017-11-5_18-2-21.png

Homework Equations



F = ma
[/B]

The Attempt at a Solution



Why is the angle 60 degrees? Isn't it 30 degrees? [/B]
 

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Lori said:
Why is the angle 60 degrees? Isn't it 30 degrees?
Because the angle is being measured from the y-axis rather than the x-axis. The angle to the x-axis is ##30^{\circ}## and the angle to the y-axis is ##60^{\circ}##.
 
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Ahhhh nevermind, i think they used the 30 degrees as the angle of the force from top left... Man. these problems are very unclear .
 
Lori said:
i think they used the 30 degrees as the angle of the force from top left... Man. these problems are very unclear .

No it's clear. The 30 degree angle on the drawing is in the correct place. P is at 30 degrees to the horizontal axis.

The vertical component of P is PCos60 or PSin30 as these are same thing.

The horizontal component of P is PSin60 or PCos30 as these are the same thing.
 

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Sorry if that was confusing, I agree with your solution.
 
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CWatters said:
Sorry if that was confusing, I agree with your solution.
No it's fine! Thanks for helping me out. I'm trying to prepare for my physics exam as much as I can! I think I really learned a lot from you guys :)
 
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