Question

A train 130 meters long crosses a platform in 30 seconds with a speed of 45 km/h. Then the length of the platform is?

• A. 270 m
• B. 245 m
• C. 280 m
• D. 296 m

Hint:

Convert all units before calculating and use total distance = train length + platform length.

Answer 1

The Correct Option is B

Step 1: Convert speed into m/s.
\[ 45 \text{ km/h} = \frac{45 \times 1000}{3600} = 12.5 \text{ m/s} \] Step 2: Use formula for distance covered when crossing a platform:
\[ \text{Distance} = \text{Speed} \times \text{Time} \] \[ = 12.5 \times 30 = 375 \text{ meters} \] Step 3: Distance covered = length of train + length of platform
Let length of platform = \(x\). Then,
\[ 130 + x = 375 \] \[ x = 375 - 130 = 245 \text{ meters} \] Hence, length of the platform is \(\boxed{245 \text{ m}}\).