# Vector Angle Problem - need help

1. Sep 2, 2007

### meganw

Vector Angle Problem - Answered, thanks! =)

1. The problem statement

Find Vector Components

2. Relevant equations

trig formulas are important here: sin =o/h, cos=a/h, tan=o/a

3. The attempt at a solution

Thanks for the help! =)

Last edited: Sep 2, 2007
2. Sep 2, 2007

### neutrino

It's just initial velocity, which has both vertical and horizontal components.

3. Sep 2, 2007

### meganw

But how do I find those components if I don't know the angle?

4. Sep 2, 2007

### neutrino

Just assign the angle some name, like $\theta_0$. Then with the given info and the equations of motion, solve for $\theta_0$.

5. Sep 2, 2007

### meganw

Thank you so much!

Last edited: Sep 2, 2007
6. Sep 2, 2007

### learningphysics

sin x must be between 0 and 1...

Actually there's one way to think about why there are two angles... Think about the range when the angle is 0 and the angle is 90... in both cases the range is 0. so the range gets larger as you go up from 0... and as you go down from 90... so that gives an intuitive reason why there are two angles for each range... for a particular range... if you have an angle close to 0... then there's another angle close to 90...

When you solve for $$\theta_0$$ two solutions will appear... note: you're restricted to angles between 0 and 90.

7. Sep 2, 2007

### neutrino

I do not know the "physical reason" behind it. But since we are talking about angles and distances, I guess I will resort to saying "the math works that way." :)

8. Sep 2, 2007

### meganw

Wow, thanks both of you!! I really appreciate it, you have no idea! =)