A train crosses a telephone pole in 25 s when it is travelling at 25 m/s. Find the length of the train (in m).

Answer

To find the length of the train, we can use the formula for distance, which is:

\[ \text{Distance} = \text{Speed} \times \text{Time} \]

### Step-by-Step Solution:

1. **Identify the given values:**
- Speed of the train (S) = 25 m/s
- Time taken to cross the telephone pole (T) = 25 s

2. **Use the formula for distance:**
- We know that the distance travelled by the train while crossing the telephone pole is equal to the length of the train. Therefore, we can write:
\[ \text{Length of the train} = \text{Speed} \times \text{Time} \]

3. **Substitute the values into the formula:**
\[ \text{Length of the train} = 25 \, \text{m/s} \times 25 \, \text{s} \]

4. **Calculate the length of the train:**
\[ \text{Length of the train} = 625 \, \text{m} \]

### Final Answer:
The length of the train is **625 meters**.

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