Calculating the components of vectors

AI Thread Summary
Vector A is directed at 41.0 degrees clockwise from the y-axis, with its x component given as -15.0. The discussion revolves around calculating the y component and magnitude of vector A, with initial calculations yielding -13.0m for the y component and 19.8m for the magnitude, which were deemed incorrect. A participant suggests using the tangent function to relate the components but realizes their calculations may be flawed, particularly in determining the y component. Another user points out that their calculation for the y component should yield -17.25, indicating a need for re-evaluation of the initial approach. Accurate calculations are essential for determining the correct vector components and magnitude.
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Vector A is in the direction 41.0 degrees clockwise from the y-axis. The x component of A is = -15.0 .

A)What is the y component of vector A?

B)What is the magnitude of vector A?

I got -13.0m for part a, and 19.8m for part b, but mastering physics says they are wrong. Any ideas?
 
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Can you post your attempt at the problem? It makes it easier to see where you might have made a mistake.
 
I kind of worked backwards since I knew that the angle is 229 degrees (41 degrees clockwise from the -y axis). And I know that the x=-15. I took tan(229) which = 1.15, which should be the fraction of the y length over the x length. Since I know the x=-15 I just solved for y to get -13.0. And then I calculated the magnitude from that, which give me 19.8.

I thought this method would work, and I am not sure where I went wrong.
 
Correction: my first post should say, 41 degrees clockwise from the -y-axis)
 
If the tangent is greater than 1, how can the y component be smaller than the x component?
 
So you did:
\displaystyle tan(229°)=\frac{A_y}{A_x}

\displaystyle A_y=A_x tan(229°)

and you're claiming that:
\displaystyle A_y=-15 tan(229°)=-13.0

right? however, I get:
\displaystyle A_y=A_x tan(229°)=-17.25

You should try re-calculating your value for Ay.
 
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