Two trains of equal length are running on parallel lines in the same direction at speeds of 90 km/h and 51 km/h. The faster train passes the slower train in 36 seconds. The length of each train is:

Correct option is C

Given:

Speeds of the trains: 90 km/h and 51 km/h

Time taken to pass = 36 seconds

Trains are of equal length

Moving in same direction

Formula Used:​

Distance = Relative Speed × Time

​Solution:

Relative Speed = (90 − 51) = 39km/h

in m/s, $$= \frac{39 \times5}{18} = \frac{65}{6} \, \text{m/s}$$​​

Distance = $$\frac{65}6 \times 36 = 390 \, \text{m}$$​​

Since both trains are equal in length:

Each Train’s Length = $$\frac{390}{2} = 195 \, \text{m}$$​​