An electric furnace is rated at $15\mathrm{kW}$ and operates on $240V$. What is the rate at which it produces heat output?

• A. $3.6\mathrm{kW}$
• B. $3600W$
• C. $15\mathrm{kW}$
• D. $225\mathrm{kW}$

Answer: (C)

Verified step by step guidance

1. Identify the given information: the electric furnace has a power rating of 15 kW and operates at 240 V. The power rating indicates the rate at which the furnace consumes electrical energy.
2. Recall that for an electric furnace, almost all the electrical power consumed is converted into heat output, since electric furnaces are designed to convert electrical energy into heat efficiently.
3. Understand that the rate of heat output is essentially the power rating of the furnace, because power is defined as energy per unit time, and here it represents the heat energy produced per second.
4. Therefore, the heat output rate is equal to the power rating of the furnace, which is 15 kW. No further calculations are needed since the power rating directly gives the heat output rate.
5. If needed, you can convert the power from kilowatts to watts by multiplying by 1000, using the formula \(\text{Power (W)} = \text{Power (kW)} \times 1000\), but the problem asks for the rate in kW, so the answer remains 15 kW.