A heater is marked 1000 W. The energy consumed by it in ten hours is

Options

A. 10J
B. 10 KJ
C. 10 kWh
D. 100 KJ

Explanation

To solve the question about the energy consumed by a heater marked 1000 W over a period of 10 hours, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Values**:
- Power of the heater (P) = 1000 W (Watts)
- Time (t) = 10 hours

2. **Convert Time to Seconds**:
- Since power in Watts is defined as Joules per second, we need to convert the time from hours to seconds.
- 1 hour = 3600 seconds
- Therefore, 10 hours = 10 × 3600 seconds = 36000 seconds.

3. **Use the Formula for Energy**:
- The formula to calculate energy (E) consumed is:
\[ E = P \times t \]
- Here, E is the energy in Joules, P is the power in Watts, and t is the time in seconds.

4. **Substitute the Values into the Formula**:
- Now substitute the values into the formula:
\[ E = 1000 \, \text{W} \times 36000 \, \text{s} \]

5. **Calculate the Energy**:
- Performing the multiplication:
\[ E = 1000 \times 36000 = 36000000 \, \text{J} \]
- Therefore, the energy consumed by the heater in 10 hours is 36,000,000 Joules.

6. **Convert Joules to Kilowatt-hours (kWh)**:
- To express the energy in kilowatt-hours, we can use the conversion factor:
\[ 1 \, \text{kWh} = 3.6 \times 10^6 \, \text{J} \]
- Thus, to convert Joules to kWh:
\[ E \, (\text{kWh}) = \frac{E \, (\text{J})}{3.6 \times 10^6} \]
- Substituting the value:
\[ E \, (\text{kWh}) = \frac{36000000}{3.6 \times 10^6} = 10 \, \text{kWh} \]

### Final Answer:
The energy consumed by the heater in 10 hours is **10 kWh**.

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