Question

The 150-meter-long train crosses the 175-meter-length platform in 13 seconds. How many km is the speed of the train?​

Answer 1

Given:

Length of the train= 150 m

Length of the platform= 175 m

Time= 13 seconds

To find:

Speed of the train

Solution:

As we know, Speed= Distance/Time

So, Distance= Length of train+ Length of platform = 325 m

So, the speed = 325/13 = 25 m/sec

To convert it into km/hour, we need to multiply it by the factor 18/5

So Speed in km/hour = 25×(18/5) = 90 km/hour

The speed of the train is 90 km/hour or 25 m/sec.

Answer 2

Solution:

Length of train = 150 m

Length of platform= 175 m

Time taken to cross platform = 13 seconds

Total distance to travel = 150 + 175 = 325 m

We added length of train and platform because as the train will cross the platform fully it will have to travel its own length too.

Speed of train = Distance traveled/Time taken

Speed of train = 325/13

Speed of train = 25 m/s

To convert from m/s to km/hr =>

1 m = 1/1000 km

1 second = 1/3600 hr

1 m/s = $\frac{\frac{1}{1000} }{\frac{1}{3600} }$ = 3600/1000 km/hr

So, 25 m/s will be,

$25 * \frac{3600}{1000} = 25 * \frac{36}{10} = 5 * \frac{36}{2} = \frac{180}{2} = 90 \ km/hr$

The speed of train to cross platform will be 25 m/s or 90 km/hr.