You have the following appliances each of 500 W running 220 V ac.
(i) Electric iron
(ii) Electric lamp
(iii) Electric room heaater
The electric resistance is

Options

A. maximum for room heater
B. maximum for electric iron
C. maximum for electric lamp
D. same in all the three cases

Explanation

To find the electric resistance of the given appliances (electric iron, electric lamp, and electric room heater), we can use the formula relating power, voltage, and resistance.

### Step-by-Step Solution:

1. **Identify the Given Values:**
- Power (P) = 500 W (for each appliance)
- Voltage (V) = 220 V (for each appliance)

2. **Use the Power Formula:**
The power consumed by an electrical appliance can be expressed using the formula:
\[ P = \frac{V^2}{R} \]
where:
- \( P \) = Power (in watts)
- \( V \) = Voltage (in volts)
- \( R \) = Resistance (in ohms)

3. **Rearranging the Formula to Find Resistance:**
We can rearrange the formula to solve for resistance \( R \):
\[ R = \frac{V^2}{P} \]

4. **Substituting the Values:**
Now substitute the known values into the equation:
\[ R = \frac{(220)^2}{500} \]

5. **Calculating the Resistance:**
First, calculate \( (220)^2 \):
\[ (220)^2 = 48400 \]
Now substitute this value into the equation:
\[ R = \frac{48400}{500} = 96.8 \, \text{ohms} \]

6. **Conclusion:**
The resistance for each appliance (electric iron, electric lamp, electric room heater) is the same because they all have the same power rating and operate at the same voltage. Thus, the resistance is:
\[ R = 96.8 \, \text{ohms} \]

### Final Answer:
The electric resistance for each appliance is **96.8 ohms**.