A train 250 metres long, running with a speed of 50 km/hr will pass an electric pole in -----

Options

A. 30 seconds
B. 18 seconds
C. 72 seconds
D. 60 seconds

Answer

To solve the problem of how long it takes for a train 250 meters long, running at a speed of 50 km/hr, to pass an electric pole, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Length of the Train**:
The length of the train is given as 250 meters.

2. **Identify the Speed of the Train**:
The speed of the train is given as 50 km/hr.

3. **Convert Speed from km/hr to m/s**:
To use the distance in meters, we need to convert the speed from kilometers per hour to meters per second. The conversion factor is:
\[ 1 \text{ km/hr} = \frac{5}{18} \text{ m/s} \]
Therefore, to convert 50 km/hr to m/s:
\[ \text{Speed in m/s} = 50 \times \frac{5}{18} = \frac{250}{18} \approx 13.89 \text{ m/s} \]

4. **Calculate the Time Taken to Pass the Pole**:
The time taken to pass the pole can be calculated using the formula:
\[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} \]
Here, the distance is the length of the train (250 meters) and the speed is approximately 13.89 m/s:
\[ \text{Time} = \frac{250 \text{ m}}{13.89 \text{ m/s}} \approx 18 \text{ seconds} \]

5. **Final Answer**:
The time taken for the train to pass the electric pole is approximately 18 seconds.

### Conclusion:
The correct option is **B) 18 seconds**.