How do you calculate the resistance of a heat strip rated at 10,000W with a voltage of 230V?

• A. R = E^2/P
• B. R = P/E
• C. R = E/P
• D. R = I^2*E

Answer: (A)

To calculate the resistance of a heat strip rated at 10,000W with a voltage of 230V, the correct approach involves using the formula for resistance derived from Ohm's Law and the power formula. The relationship between power (P), voltage (E), and resistance (R) can be expressed as:

1. The formula for electric power is ( P = \frac{E^2}{R} ).

2. Rearranging this formula to solve for resistance gives ( R = \frac{E^2}{P} ).

Given that the voltage (E) is 230V and the power (P) is 10,000W, you substitute these values into the rearranged formula:

( R = \frac{(230)^2}{10000} ).

This method effectively utilizes the square of the voltage divided by power to yield the resistance.

Choosing this formula is appropriate because it directly relates the electrical quantities involved—voltage and power—providing a clear pathway to determine the resistance of the system.