# Crow flying to destination (vector problem)

1. Sep 1, 2014

### LoganPatrick

1. The problem statement, all variables and given/known data
A crow flies in two successive displacements to a point that is 80 m to the west. Its first displacement is 80 m in a direction θ1 = 65° west of north.

a)What is the magnitude of its second displacement?

b)What is its direction of its second displacement measured by the angle θ2 measured west from north?

2. Relevant equations

3. The attempt at a solution

90-65= 25° N of W

cos25°= 80/c --> then c= 80/cos25°= 88.3m

c²=a²+b²

b=√(c²-a²)
b=√((88.3)²-(80)²)
b=37.4m

180°= 25°+90²+Θ
Θx=65°

360°-65°=

295° W of N

2. Sep 1, 2014

### BvU

Hello Patrick, and welcome to PF.

In these cases a sketch or a drawing is a big help. I, for instance, can't understand what the c you are calculating, stands for.

I can understand the 25°, though, and I can calculate how much of the 80 m in the westward direction has been covered (call it A). Also how much in the northward direction (call it B). So all I, crow, have to do then is to go west the remainder of the 80 m and south the same distance B. Gives me a magnitude using Pythagoras and an angle via an arctangent.

3. Sep 1, 2014

### phinds

What is ALWAYS advised here is that when you want help with such a problem, SHOW YOUR DIAGRAM. That lets us know what you are doing/thinking and might readily lead to our being able to help you.