# Homework Help: Electric charge inside a uniformly distributed sphere

1. Apr 5, 2015

### Caglar Yildiz

1. The problem statement, all variables and given/known
my book says inside of a uniformly distributed sphere is zero and it also says it is not it is increasing. I didnt understand any single thing it is like kidding me?

2. Relevant equations

3. The attempt at a solution

2. Apr 5, 2015

### Sergey Vilov

Could you say exactly what the book states?

Actually, in electrostatics the electric field is always zero in conductors. The usual explanation is that conductors are always in the external electric field created by all of the other charges in the world. This field render the conductor to redistribute charges inside in order to create an internal electric field which eliminates the external electric field. Hence, there are two electric fields in the conductor of the same magnitude but the opposite direction. Their sum gives zero.

Perhaps, this is meant in the book.

3. Apr 5, 2015

### Caglar Yildiz

It isn't conductor in spherical suface electrical field is not zero but in hollow it is. That is the problem a sphere is made of hollows so why would it not be zero

4. Apr 5, 2015

### Staff: Mentor

The electric field inside a conductor is zero everywhere, independent of the geometry. If you remove the interior material but do not add additional charges, the electric field is still zero.

5. Apr 6, 2015

### Sergey Vilov

If you have an abstract sphere of positive(negative) charges, imagine how electric field lines go. Their general property is that they should start at positive charges and end at negative charges. Imagine them going from each elementary charge of the sphere. As there is no negative(positive) charge inside, these lines can't go inside.Otherwise, they would have to end at positive charges of the sphere. This means that there is no electrical field inside the sphere.

6. Apr 6, 2015

### Caglar Yildiz

Thanks i think i got it