Question

A train running at speed of 90 km/hr crosses a platform double its length in 36 sec.what is the length of the platform in metre

Answer 1

the length of the platform is 2160m

Answer 2

Answer:

The length of platform is 450 m.

Step-by-step explanation:

Given : A train running at speed of 90 km/hr crosses a platform double its length in 36 sec.

To find : What is the length of the platform in meter.

Solution : Let d be the distance or length of the platform.

We have given a platform double its length = 2d

Speed of train = 90 km/hr

Convert into m/s,

1 km/hr = $\frac{5}{18}$ m/s

90 km/hr = $90\times\frac{5}{18}$ m/s

90 km/hr = $25$ m/s

Speed s=25 m/s

Time = 36 sec

$\text{Distance}=\text{Speed}\times\text{Time}$

$2d=\text{s}\times t$

$2d=25\times 36$

$2d=900$

$d=\frac{900}{2}$

$d=450$

Therefore,The length of platform is 450 m.