CAT 2021 Slot 1 QA Question 3: Two trains cross each other in 14 seconds when running in opposite directions along parallel tracks. The faster train is 160 m long and crosses a lamp post in 12 seconds. If the speed of the other tra

Question

Two trains cross each other in 14 seconds when running in opposite directions along parallel tracks. The faster train is 160 m long and crosses a lamp post in 12 seconds. If the speed of the other tra

Accepted Answer

The faster train crosses a lamp post in 12 seconds. So its speed is length divided by time.
$\dfrac{160}{12} = \dfrac{40}{3}$
That is 48 km/hr.
The other train is 6 km/hr slower, so its speed is 42 km/hr. In m/s, this is
$42 	imes \dfrac{5}{18} = \dfrac{35}{3}$
The relative speed in opposite direct

Two trains cross each other in 14 seconds when running in opposite directions along parallel tracks. The faster train is 160 m long and crosses a lamp post in 12 seconds. If the speed of the other train is 6 km/hr less than the faster one, its length, in m, is