# Circular trajectory question

1. Sep 12, 2009

### Emethyst

1. The problem statement, all variables and given/known data
An object travels in a circular trajectory that has a diameter of 4m. From start to finish the change in the angle of movement is 45 degrees. How far has the object travelled?

2. Relevant equations
Circumference formula

3. The attempt at a solution
I started by drawing out a circle and filling in the info given. From what was supplied in the question, I decided to use the circumference formula and then divide the answer obtained by 8 to take into account the change of angle. The answer I came up with was 1.6m. I'm not sure if this is correct because i'm not supposed to have to use a calculator to come up with the answer, so i'm not sure if i'm doing something wrong. If anyone can point out any mistakes I could've made it would be greatly appreciated, thanks in advance.

2. Sep 12, 2009

### rock.freak667

In 360 degrees it travels πd meters
in 45 degrees how far does it go??