Question

23. Two trains of length 125 meters and 115 meters are running on parallel tracks. When they run in the same direction the faster train crosses the slower train in
when they run in opposite direction they cross each other in 10 seconds. What is the speed of each train?
O 15,8
16,9
None of these
O 16,8​

Answer 1

Answer:

Let the speed of second train is = x km/hr time =l1+l2Relative speed in oppo. direction

6=(125+125)(65+x)×518

6=(250×18)(65+x)×5

65+x=50×3

x=150−65

x=85 km/hr

Answer 2

Let the speed of faster train = X m/sec

Let the speed of slower train= Y m/sec

Then, relative speed when they are moving in opposite direction = X + Y

Apti Problem on trains 69

10X + 10Y = 240

X + Y = 24

Y = 24 − X ................ (1)

Relative speed when they are moving in same direction = X − Y

Apti Problem on trains 70

30X − 30Y = 240

3X − 3Y = 24

X − Y = 8 ............... (2)

Put the value of Y from equation (1) to equation (2)

X − (24 − X) = 8

X − 24 + X = 8

2X = 8 + 24

2X = 32

X = 16 m/sec

Put the value of X in equation (1) to find value of Y;

Y = 24-16 = 8 m/sec.