# Find the components of a unit vector

## Homework Statement

http://i.imgur.com/B1hFY6E.png

## Homework Equations

-Basic geometry
-Similar triangles (?)
-Pythagorean Theorem

## The Attempt at a Solution

-I need to find the angle the bar AB makes with the horizontal, correct? And with that, I will be able to figure out the components for the unit vector...
-I'm stuck at where exactly to start. I feel as though there are generalizations I am not making that are necessary to begin....

## Answers and Replies

SteamKing
Staff Emeritus
Science Advisor
Homework Helper
Draw a picture of the curved bar and lay out the straight bar as shown on the diagram. Can you figure out the components of the vector AB? Remember the length of AB is given.

rude man
Homework Helper
Gold Member

## Homework Statement

http://i.imgur.com/B1hFY6E.png

## Homework Equations

-Basic geometry
-Similar triangles (?)
-Pythagorean Theorem

## The Attempt at a Solution

-I need to find the angle the bar AB makes with the horizontal, correct? And with that, I will be able to figure out the components for the unit vector...
-I'm stuck at where exactly to start. I feel as though there are generalizations I am not making that are necessary to begin....

Draw a line from the origin to B. You know this distance, right? So you have all 3 sides of a triangle & from that you can determine your angle using law of cosines.