Question

A Train travelling at a uniform speed clears a platform 200 m long in 10 seconds and passes a telegraph post in 5 seconds. The speed of the train is *

Answer 1

Given :-

• Train Passes a platform of 200m in 10 seconds.
• Train passes a Telegraph Pole in 5 seconds.
• The Speed of Train is ? .

Answer :-

Let us Assume That, The Speed of Train is x m/s and Length of Train is y m.

Than ,

in Passing a Telegraph Pole in 5 seconds, The Train Cover Distance Equal to Length of Train.

So,

→ Speed = (Distance/Time) .

→ x = (y/5) m/s. ------------------------- Equation (1)

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Now, in Passing a Platform The Train will cover Distance Equal to Sum of Length of Platform and Length of Train .

So,

→ Speed = ( Total Distance / Time)

→ x = (y + 200) / 10 m/s ------------------- Equation (2) .

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Comparing Both Equations Now, we get,

→ (y/5) = (y+200)/10

→ 10y = 5(y + 200)

→ 10y = 5y + 1000

→ 10y - 5y = 1000

→ 5y = 1000

→ y = 200m.

Putting This Value in Equation (1) now, we get,

→ x = (200/5)

→ x = 40m/s.

Or,

→ x = 40 * (18/5)

→ x = 144km/h.

Hence, Speed of Train is 144km/h.