Two trains are moving towards each other with the speed of 25 km/hr and 83 km/hr respectively. What will be the distance (in metres) between the trains one second before collide?

Options

A. 32
B. 35
C. 30
D. 40

Answer

To solve the problem step by step, we need to find the distance between two trains one second before they collide, given their speeds.

### Step-by-Step Solution:

1. **Identify the Speeds of the Trains**:
- Train A is moving at 25 km/hr.
- Train B is moving at 83 km/hr.

2. **Calculate the Relative Speed**:
- Since the trains are moving towards each other, their relative speed is the sum of their individual speeds.
\[ \text{Relative Speed} = \text{Speed of Train A} + \text{Speed of Train B} = 25 \text{ km/hr} + 83 \text{ km/hr} = 108 \text{ km/hr} \]

3. **Convert the Relative Speed from km/hr to m/s**:
- To convert km/hr to m/s, we use the conversion factor \( \frac{5}{18} \).
\[ \text{Relative Speed in m/s} = 108 \times \frac{5}{18} = 30 \text{ m/s} \]

4. **Calculate the Distance Covered in 1 Second**:
- The distance covered by the trains in one second, which is the distance between them one second before they collide, can be calculated using the formula:
\[ \text{Distance} = \text{Speed} \times \text{Time} \]
- Here, the time is 1 second.
\[ \text{Distance} = 30 \text{ m/s} \times 1 \text{ s} = 30 \text{ meters} \]

5. **Conclusion**:
- The distance between the two trains one second before they collide is **30 meters**.

### Final Answer:
The distance between the trains one second before they collide is **30 meters**.

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