Question

A train 350 m long travelling at a speed of 60km/h crosses a platform in 48 seconds. What is the length of the platform?​

Answer 1

Answer :-

Length of the platform = 450 m

Solution :-

Length of the train = 350 m

Speed of the train = 60 Km/h

Time taken to cover the platform by train (t) = 48 seconds

First convert speed into m/s

Multiply speed with 5/18

Speed in m/s = 60 * 5/18 = 10 * 5/3 = 50/3

So speed (s)= 50/3 m/s

Distance traveled by train to cross a platform(d) = Length of the train + Length of the platform

Let the length of the platform be 'x' m

Distance traveled by train to cross a platform(d) = (350 + x) m

$\boxed{ \sf Speed = \dfrac{Distance}{Time} }$

Here

Speed (s) = 50/3 m/s

Distance (d) = (350 + x) m

Time (t) = 48 seconds

$\tt \implies \dfrac{50}{3} = \dfrac{350 + x}{48}$

By cross multiplication

⇒ 50(48) = (350 + x)3

⇒ 2400 = 1050 + 3x

⇒ 2400 - 1050 = 3x

⇒ 1350 = 3x

⇒ 1350/3 = x

⇒ 450 = x

⇒ x = 450

Therefore length of the platform is 450 m.

Answer 2

Answer:

Length of the train = 350 m

Speed of the train = 60 Km/h

Time taken to cover the platform by train (t) = 48 seconds

First convert speed into m/s

Multiply speed with 5/18

Speed in m/s = 60 * 5/18 = 10 * 5/3 = 50/3

So speed (s)= 50/3 m/s

Distance traveled by train to cross a platform(d) = Length of the train + Length of the platform

Let the length of the platform be 'x' m

Distance traveled by train to cross a platform(d) = (350 + x) m

\boxed{ \sf Speed = \dfrac{Distance}{Time} }

Speed=

Time

Distance

Here

Speed (s) = 50/3 m/s

Distance (d) = (350 + x) m

Time (t) = 48 seconds

\tt \implies \dfrac{50}{3} = \dfrac{350 + x}{48}⟹

3

50

=

48

350+x

By cross multiplication

⇒ 50(48) = (350 + x)3

⇒ 2400 = 1050 + 3x

⇒ 2400 - 1050 = 3x

⇒ 1350 = 3x

⇒ 1350/3 = x

⇒ 450 = x

⇒ x = 450

Therefore length of the platform is 450 m.