A parallel-plate capacitor having plate are `100 cm ^2` and separation 1.0 mm holds a charge of `0.12 muC` when connected to a 120 V battery. Find the dielectric constant of the material filling the gap.

Explanation

To find the dielectric constant (K) of the material filling the gap of a parallel-plate capacitor, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Values:**
- Plate area (A) = 100 cm² = \(100 \times 10^{-4}\) m² = \(1 \times 10^{-2}\) m²
- Plate separation (D) = 1 mm = \(1 \times 10^{-3}\) m
- Charge (Q) = 0.12 µC = \(0.12 \times 10^{-6}\) C
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