Question

A train 240 m long passes an electric pole in 16 seconds .Find: (i) the speed of the train in km/h .(ii) the time taken by it to cross a platform 180 m long .(with statements)

Answer 1

1. Speed of the train= distance/ time
= (240/16)m/s-1
=15m/s-1
2.time by train=distance/speed
=(180/15)seconds
=12 seconds.

Answer 2

Answer:

(i)  $\text{Speed}=54.54\text{ km/hr}$

(ii)  $\text{Time}=3.3$

Step-by-step explanation:

Given : A train 240 m long passes an electric pole in 16 seconds.

To find : (i) The speed of the train in km/h.

(ii) The time taken by it to cross a platform 180 m long.

Solution :

(i) Distance = 240 m

Convert m into km,

1 km= 1000 m

1 m= 0.001 km

240 m= 0.24 km

Time = 16 seconds

Convert seconds into hours,

1 h= 3600 s

1 s = $\frac{1}{3600}$ hr

16 s =  $\frac{16}{3600}$ hr

16 s = 0.0044 hr

We know, $\text{Speed}=\frac{\text{Distance}}{\text{Time}}$

$\text{Speed}=\frac{0.24}{0.0044}$

$\text{Speed}=54.54\text{ km/hr}$

(ii) Distance = 180 m

Into km, D=0.18 km

Speed = 54.54 km/hr

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

$\text{Time}=\frac{180}{54.54}$

$\text{Time}=3.3$