(46) Two trains of lengths 530 meters and 630 meters are running on parallel lines in the opposite direction at 45 km/hr and 95 km/hr. In how many seconds will the trains pass each other?
Answer :29.81
Explanation
Relative speed = Speed of Train 1 + Speed of Train 2
Relative speed = 45 km/hr + 95 km/hr = 140 km/hr
Now, we need to convert the relative speed from km/hr to meters/sec:
(140 km/hr) * (1000 m/km) * (1 hr/3600 sec) = 38.89 m/sec (approximately)
Next, we find the total length the trains need to cover to pass each other completely. This is equal to the sum of their lengths:
Total length = Length of Train 1 + Length of Train 2
Total length = 530 m + 630 m = 1160 m
Now, we can find the time it takes for the trains to pass each other by dividing the total length by their relative speed:
Time = Total length / Relative speed
Time = 1160 m / 38.89 m/sec ≈ 29.81 seconds (approximately)
So, it will take about 29.81 seconds for the two trains to pass each other completely.
(47) Two trains of equal length are running on parallel lines in the opposite direction at 40 km/hr and 100 km/hr. The trains pass each other in 50 seconds. The length of each train is?
Answer : 111.11
Explanation
The relative speed of the trains is 40 + 100 = 140 km/hr.
140 km/hr = 140000 m / 3600 s = 400/9 m/s
The length of each train is 400/9 * 50/2 = 1000/9 = 111.11 m
So the answer is 111.11
