A 240-metre long train crosses a platform twice its length in 2 minutes . What is the speed of the train ?

Options

A. 8 m/s
B. 4 m/s
C. 6 m/s
D. Cannot be determined

Explanation

To find the speed of the train that crosses a platform twice its length in 2 minutes, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Length of the Train:**
The length of the train is given as 240 meters.

2. **Calculate the Length of the Platform:**
The platform is twice the length of the train. Therefore, the length of the platform is:
\[ \text{Length of the platform} = 2 \times \text{Length of the train} = 2 \times 240 = 480 \text{ meters} \]

3. **Calculate the Total Distance Covered:**
When the train crosses the platform, it covers the length of the train plus the length of the platform:
\[ \text{Total distance} = \text{Length of the train} + \text{Length of the platform} = 240 + 480 = 720 \text{ meters} \]

4. **Convert Time from Minutes to Seconds:**
The time taken to cross the platform is given as 2 minutes. We need to convert this into seconds:
\[ \text{Time in seconds} = 2 \times 60 = 120 \text{ seconds} \]

5. **Calculate the Speed of the Train:**
Speed is calculated as the total distance divided by the time taken:
\[ \text{Speed} = \frac{\text{Total distance}}{\text{Time}} = \frac{720 \text{ meters}}{120 \text{ seconds}} = 6 \text{ meters per second} \]

### Final Answer:
The speed of the train is **6 meters per second**.

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