# Homework Help: Magnitude and direction of Vectors using head to tail rule

1. Jan 2, 2013

2. Jan 2, 2013

### MrWarlock616

I think you've got the directions wrong. The x-component of forces are in opposite directions, so you need to account for that.

You've calculated the y-component of the resultant correctly, but even there you haven't specified the downward direction which could cause you to lose marks sometimes.

Since, your calculation for x-components is wrong, the magnitude and direction of the resultant is also wrong...

3. Jan 2, 2013

### Staff: Mentor

the first two look okay the last page #3 you used vector length value so your tan angle is wrong.

A quick way to check your solution is to graph it and take measurements for the angle and length to see that your results agree.

4. Jan 2, 2013

### MrWarlock616

Shouldn't Fx=-6000cos(60°)+2000cos(45°)?

5. Jan 2, 2013

### Staff: Mentor

Yes, I think you're right. I didn't notice that.

6. Jan 2, 2013

### bllnsr

so after doing Fx=-6000cos(60°)+2000cos(45°)
resultant force is 6797.915 correct?

7. Jan 2, 2013

### MrWarlock616

Yes. And what will be the angle made by that resultant with the positive x-axis??

8. Jan 2, 2013

### bllnsr

$tan\theta = f_y/F_x$
180-76.51= 103.48
right?

9. Jan 2, 2013

### MrWarlock616

Correct! :)

10. Jan 2, 2013

### bllnsr

Thanks for the help