# Help (: adding vectors! components... angles, drawing.

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1. Jul 9, 2017

### britt6

1. The problem statement, all variables and given/known data
A ship travelling 55 degrees [W of N] is 65km farther north after 3.0h. What is the ship's velocity.

2. Relevant equations
sin, cos, tan?

3. The attempt at a solution
I know that Vground= Vair + Vwind, and that Vground = Vboat + Vcurrent, but i'm not sure if that is even relevant to the question... So far I have drawn out :

Do I add these vectors together or subtract? and am I trying to find the boat's velocity or ground velocity. I think boat velocity but what does that make of the 55 degrees W of N... I am so lost please help (:

Last edited: Jul 9, 2017
2. Jul 9, 2017

### NFuller

You need to show some attempt at a solution first before others will try to help you.
Try drawing out the problem at least.

3. Jul 9, 2017

### britt6

Ok! ive never used this before lol so I don't know what I'm doing. But thanks, I will do that.

4. Jul 9, 2017

### Staff: Mentor

Your image link appears to be addressing a target that is not publicly accessible. I suggest that you UPLOAD the image file to the PF server so that it's made available t our homework helpers (use the UPLOAD button).

5. Jul 9, 2017

Thank you!!!

6. Jul 9, 2017

### Staff: Mentor

On your image you've labelled the distances x and y. y is the distance that the boat traveled in the northward direction, and presumably x is distance it traveled in the westward direction. Can you determine the total distance it traveled along its trajectory? (hint: what's the length of the hypotenuse of that triangle?)

7. Jul 9, 2017

### britt6

Now im not sure... Do I use v=d/t. The answer in the book says its 38km/h but that doesn't seem to match up with my numbers.

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8. Jul 9, 2017

### Staff: Mentor

Your evaluation of c doesn't look right. Please show your calculation in detail. What is a? What is b?

9. Jul 9, 2017

### britt6

Oops I see where I made a mistake.. instead of putting a as 65 squared, I put 95 squared. Just a calculation error! Thanks for your help, I've figured out the question now (: