The filament of a bulb takes a current 100 mA when potential difference across it is 0-2 V. When the potential difference across it becomes 1.0 V, the current becomes 400 mA. Calculate the resistance of the filament in each case and account for the difference.

Explanation

To solve the problem, we will calculate the resistance of the filament in two different cases using Ohm's Law, which states that \( R = \frac{V}{I} \).

### Step 1: Calculate Resistance for Case 1
- **Given:**
- Current \( I_1 = 100 \, \text{mA} = 100 \times 10^{-3} \, \text{A} = 0.1 \, \text{A} \)
- Voltage \( V_1 = 0.2 \, \text{V} \)

- **Using Ohm's Law:**
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