A new unit of length is chosen such that the speed of sound at room temperature is taken as unit. The sound of an explosion reaches a listener in 10s. Find the distance between the listener and the place where explosion took place.

Explanation

To solve the problem, we need to find the distance between the listener and the place where the explosion took place, given that the speed of sound is taken as a new unit of length.

### Step-by-Step Solution:

1. **Identify the Speed of Sound**:
- The problem states that the speed of sound at room temperature is taken as the unit of length. Let's denote this speed as \( 1 \) unit of distance.

2. **Identify the Time Taken**:
- The sound of the explosion reaches the listener in \( 10 \) seconds.

3. **Use the Formula for Distance**:
- The formula to calculate distance when speed and time are known is:
\[ \text{Distance} = \text{Speed} \times \text{Time} \]

4. **Substitute the Known Values**:
- Here, the speed is \( 1 \) unit (the speed of sound), and the time is \( 10 \) seconds. Therefore, we can substitute these values into the formula:
\[ \text{Distance} = 1 \, \text{unit} \times 10 \, \text{seconds} \]

5. **Calculate the Distance**:
- Performing the multiplication gives:
\[ \text{Distance} = 10 \, \text{units} \]

6. **Conclusion**:
- The distance between the listener and the place where the explosion took place is \( 10 \) units.

### Final Answer:
The distance between the listener and the place where the explosion took place is \( 10 \) units.

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