Finding velocity components with Forces?

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SUMMARY

The discussion centers on calculating the velocity components of an object subjected to three forces: F1 = (−1.85i + 6.35j) N, F2 = (4.90i − 1.15j) N, and F3 = (−44.5i) N, resulting in an acceleration of 3.55 m/s². The user correctly determined the acceleration direction as 169.74 degrees and calculated the speed after 14 seconds as 49.7 m/s. However, there is confusion regarding the calculation of the y-component of velocity (vy), where the user incorrectly used the angle 169.74 degrees instead of 10.26 degrees, leading to an erroneous result. The community suggests verifying the angle used in the sine calculation.

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JessicaJ283782
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Three forces acting on an object are given by F1 = (−1.85i+ 6.35j) N, F2 = (4.90i − 1.15j) N, and F3 = (−44.5i) N. The object experiences an acceleration of magnitude 3.55 m/s2.

They want the velocity components of the object after 4 seconds.

First, I calculated the direction of the acceleration to be 169.74 degrees, which it says is correct.

So, I went and calculated its speed after 14 seconds, and I got 49.7 m/s and it says its right.

Then, I went and and calculated vx=49.7*cos(169.74) and got it right.

However, when I go to calculate vy=49.7*sin(169.74), it says its wrong but "I calculated the y component correctly using my incorrect values from above". Yet I got all of the above information right...can anyone help if I'm doing something wrong when calculating vy?

Thanks!
 
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maybe you try inputing 49.7*sin(10.26).
 
Check the math ... I don't get the same angle you calculated. Or apparently what the answer key has calculated. Maybe you wrote it down wrong? Please show your work.
 

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