# Find electric field on a point due to a charged arc.

1. Sep 13, 2013

### cgar666

1. The problem statement, all variables and given/known data
A charge of 25nC is uniformly distributed along a circular arc (radius = 2.0 m) that is subtended by a 90-degree angle. What is the magnitude of the electric field at the center of the circle along which the arc lies?

I'm not getting the right answer however, so if someone would be able to help me solve this question and point out what I'm doing wrong I"d be very appreciative.

2. Relevant equations
E = k*Q/r^2
θ=s/r
dq = λ ds

3. The attempt at a solution

2. Sep 13, 2013

### Tanya Sharma

The limits of integration should be $\frac{-\pi}{4}$ to $\frac{\pi}{4}$.

The arc length is $\frac{(2)(\pi)(r)}{4}$.

3. Sep 13, 2013

### Bryson

No, cgar666 limits of integration are perfectly fine. They may just lead to more math. You can use symmetry to slightly clean up some algebra as well.