# Finding velocity components with Forces?

1. Feb 2, 2014

### JessicaJ283782

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!

2. Feb 2, 2014

### td21

maybe you try inputing 49.7*sin(10.26).

3. Feb 2, 2014

### PhanthomJay

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.