What is the angle that \vec{C} makes with the positive x axis?

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The discussion revolves around finding the angle that vector \vec{C} makes with the positive x-axis, given its length and angle with the y-axis. Initial calculations yielded incorrect components, leading to confusion about the angle's reference. Participants clarify that the angle should be measured starting from the positive x-axis and moving counterclockwise. A miscalculation resulted in an incorrect angle of 600 degrees, which was corrected by emphasizing the proper quadrant system. The conversation concludes with confirmation of the correct approach to determining the angle.
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Homework Statement


Find the components of the vector \vec{C} with length c = 1.00 and angle \phi = 30.0^{\circ} as shown.

NV_ct.jpg


Homework Equations


opp=hypcos(\theta)
adj=hypcos(\theta)


The Attempt at a Solution



tried to use the above equations to answer the question, however when i looked in the answers it was incorrect.
Answer i got was x=0.866 and y=0.5

When i realized that it was between the vector and the y axis, i found that the angle didn't make contact with the x-axis, so my question is What is the angle that \vec{C} makes with the positive x axis?

P.S
 
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Hi Paymemoney! :smile:
Paymemoney said:

Homework Equations


opp=hypcos(\theta)
adj=hypcos(\theta)

erm :redface: … they can't both be right, can they? :biggrin:
When i realized that it was between the vector and the y axis, i found that the angle didn't make contact with the x-axis, so my question is What is the angle that \vec{C} makes with the positive x axis?

Start at the positive x-axis, go round to the y-axis, then go round some more … that's your angle! :wink:

But the main thing you've done wrong is that the dotted line marked "x" on your diagram isn't x, is it? :smile:
 
tiny-tim said:
Hi Paymemoney! :smile:


erm :redface: … they can't both be right, can they? :biggrin:

oops, meant to be opp=hypsin(\theta)

tiny-tim said:
Start at the positive x-axis, go round to the y-axis, then go round some more … that's your angle! :wink:

But the main thing you've done wrong is that the dotted line marked "x" on your diagram isn't x, is it? :smile:

ok so i got 600 degrees, what is the next step i should take to solve \vec{C}
 
Hi Paymemoney! :smile:

(have a degree: º and a theta: θ and a phi: φ :wink:)
Paymemoney said:
ok so i got 600 degrees …

hold it!

however did you get 600º ? :confused:
 
well i went around the the axis 2 times o_o
 
Paymemoney said:
well i went around the the axis 2 times o_o

Still not 600º. :confused:

Anyway, just go from the x-axis to the y-axis anticlockwise, and then carry on to C.
 
ok this is what i have done:

vectorquess.JPG


tell me if this is correct.
 
Yes, that's exactly correct. :smile:

The "first quadrant" (top-right) is 0º to 90º, the "second quadrant" (top-left) is 90º to 180º, and so on. :wink:
 
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