- #1

Yalanhar

- 39

- 2

- Homework Statement
- A thin rod of length L and charge Q is uniformly charged, so it has a linear charge

density ##\lambda =q/l## Find the electric field at point where is an arbitrarily positioned

point.

- Relevant Equations
- ##dE=\frac{Kdq}{r^2}##

**Homework Statement:**A thin rod of length L and charge Q is uniformly charged, so it has a linear charge

density ##\lambda =q/l## Find the electric field at point where is an arbitrarily positioned

point.

**Homework Equations:**##dE=\frac{Kdq}{r^2}##

A thin rod of length L and charge Q is uniformly charged, so it has a linear charge

density ##\lambda =q/l## Find the electric field at point P where P is an arbitrarily positioned

point.

Tipler solves this one. But there are 2 things that I do not understand about his solution.

1) Why on 5 he used the negative sign for Xs? shouldn't he use Xs positive as in:

##tan\theta =\frac {y}{x}##

##x = \frac{y}{tan\theta}##

##dx = -ycsc^2\theta##

But by doing this my Ex gets negative.

2) What the negative sign on Ey means? The orientation is opposite to the unit vector j?

Sorry for bad image and english.