# Homework Help: Displacement question

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1. Feb 15, 2015

### Rasofia

1. The problem statement, all variables and given/known data

Lorraine steered her boat out of the harbor, heading east. She travelled 500 m to one buoy and then turned north and headed 300 m to another buoy. Jeff also left the harbor from the same point, and travelled 300 m [N] to a buoy, and then went 500 m [E].
a) What is the position of Jeff's boat relative to Lorraine's boat after they finish moving?
b) If Lorraine and Jeff race straight back, in what direction are they headed?

2. Relevant equations

3. The attempt at a solution
Okay, for letter a, I was a bit confused because are they not in the same position? They end up in the same place. But I guess technically Jeff's position would be west relative to Lorraine's boat?
For letter b, I said southwest, because they first go north east. Correct or not?

2. Feb 15, 2015

### Bystander

Unless he rammed her and one or both boats sank.
SW is good. There is a possibility that they want a compass heading in degrees. Remember enough trig to calculate that?

3. Feb 15, 2015

### Rasofia

I used tangent inverse (y/x) and got around 31 degrees so maybe that's it?
I don't really know if that would be the right equation for this though.

4. Feb 15, 2015

### Bystander

That's perfectly good. Compass headings for mariners start with 0 degrees at due north, proceed clockwise through 90 (E), 180 (S), 270 (W), and back to 360 (a full circle) reset to 0 (N). So you've got 270 - 31 rather than 225 which would be a nitpicker's SW. Hand them the number and SW or WSW and you are in business.