We have a `30 W, 6 V` bulb , which we want to glow by a supply of `120 V` . What can be done for this ?

Explanation

To glow a 30 W, 6 V bulb using a 120 V supply, we need to ensure that the voltage across the bulb does not exceed its rated voltage. This can be achieved by using a series resistor. Here’s the step-by-step solution:

### Step 1: Calculate the resistance of the bulb
The power (P) and voltage (V) ratings of the bulb are given as:
- Power, P = 30 W
- Voltage, V = 6 V

Using the formula for resistance:
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