Force Relative to the vertical?

AI Thread Summary
Cosine theta is vertical and sine theta is horizontal because of the angle's definition in relation to the force vector. In the example provided, theta is measured between the force vector and the vertical axis, which determines the orientation of the sine and cosine functions. If theta were defined between the force vector and the horizontal axis, the roles of sine and cosine would indeed switch. This distinction is crucial for understanding vector components in physics. Clarifying the angle's reference point helps resolve confusion about trigonometric relationships.
Scorry
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Can you explain why cosine theta is vertical, and sin theta is horizontal on this example? I am confused.
 
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Scorry said:
Can you explain why cosine theta is vertical, and sin theta is horizontal on this example? I am confused.

Link?

Does it look like this?

https://www.cdli.ca/sampleResources/physics3204/unit01_org02_ilo03/u01-s02-ls03-lessonfig07.gif
u01-s02-ls03-lessonfig07.gif
 
Thanks. I attached a photo, but it's not showing up. Your example is what we're covering next, I haven't gotten there yet.
image.jpeg
image.jpeg
 
It's because of which angle theta they are using (they show theta between the force vector and the vertical axis). If they defined/chose theta to be between the force vector and the horizontal axis, that would switch the sin() and cos() terms, right?
 
berkeman said:
It's because of which angle theta they are using (they show theta between the force vector and the vertical axis). If they defined/chose theta to be between the force vector and the horizontal axis, that would switch the sin() and cos() terms, right?
Thanks man, it makes a little more sense. I haven't taken trig in a few years.
 
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