Question

A train speeding at $120$ km/hr crosses an electric pole in $9$ seconds and a platform in $24$ seconds. What is the length of the platform?

• A. $500$ m
• B. $800$ m
• C. $300$ m
• D. $1100$ m

Answer 1

The correct option is A $500$ m

Speed of train $=120km/hr=120\times \frac{5}{18}m/s=\frac{100}{3}m/s$

Time taken to cross the electric pole = 9 sec

$\therefore$ Length of the train $=(\frac{100}{3}\times 9)m=300m$

Let the length of the platform be x m.

Then a distance of (x + 300) m is to be covered in 24 seconds at speed of $\frac{100}{3}m/s$

$\therefore (x+300)=(\frac{100}{3}\times 24)m$

$\Rightarrow x+300=800$

$\Rightarrow x=500m$