A sphere of radius r, encloses a net charge Q. If there is another concentric sphere `S_(2)` of radius `r_(2)(r_(2)gtr_(1))` enclosing charge 20, find the ratio of the electric flux through `S_(1)` and `S_(2)`. How will the electric flux through sphere `S_(1)` change, if a medium of dielectric constant k is introduced in the space inside `S_(2)` in place of air?

Explanation

To solve the problem, we will follow these steps:

### Step 1: Understand the setup
We have two concentric spheres:
- Sphere \( S_1 \) with radius \( r_1 \) enclosing a charge \( Q \).
- Sphere \( S_2 \) with radius \( r_2 \) (where \( r_2 > r_1 \)) enclosing a charge \( 20Q \).

### Step 2: Use Gauss's Law
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