Question

A train which is travelling at a constant speed crosses a lamp post in 9 seconds and it takes 13.5 seconds to cross a platform 99 m long. Find the length of the train.​

Answer 1

Question:-

A train which is travelling at a constant speed crosses a lamp post in 9 seconds and it takes 13.5 seconds to cross a platform 99 m long. Find the length of the train.

To Find:-

• Find the length of the train.

Solution:-

First ,

We have to find the time taken to cross:-

$\sf\longrightarrow \: Time = 13.5 - 9$

$\sf\longrightarrow \: Time = 4.5$

Now ,

We have to find the speed of train:-

$\sf\longrightarrow \: Speed = \dfrac { distance } { time }$

$\sf\longrightarrow \: Speed = \cancel\dfrac { 99 } { 4.5 }$

$\sf\longrightarrow \: Speed = 22 \: m/s$

Now ,

We have to find the distance travelled:-

$\sf\longrightarrow \: Distance = \dfrac { 22 } { 9 } \times 9$

$\sf\longrightarrow \: Distance = 22 \: m$

Hence ,

• Distance travelled is 22m