Rubber balloon in electric field

[phantom113]

Homework Statement

A rubber balloon has a charge q evenly distributed over its surface. It is put into a uniform electric field of 120 N/C. What is the charge inside the balloon?

Homework Equations

The Attempt at a Solution

I thought that E inside would be 120 since before it is put into the electric field, E inside is 0(true or not?). When it is put into the field you use the principle of superposition and they add to 120 N/C?

Any insight to this would be helpful. I handed it in this morning but I'd still like to know if I made correct assumptions.

 

[dark adonis]

Homework Statement

A rubber balloon has a charge q evenly distributed over its surface. It is put into a uniform electric field of 120 N/C. What is the charge inside the balloon?

Homework Equations

The Attempt at a Solution

I thought that E inside would be 120 since before it is put into the electric field, E inside is 0(true or not?). When it is put into the field you use the principle of superposition and they add to 120 N/C?

Any insight to this would be helpful. I handed it in this morning but I'd still like to know if I made correct assumptions.

Assuming the balloon to approximate a spherical shell then I'd say you're right about the E-field, but you are missing a step, which is using the polarizability to relate the field to the dipole moment created and ultimately the charge on the inside.