A train of length 150 metres takes 10seconds to pass over another trai

1.	A train of length 150 metres takes 10seconds to pass over another train 100metres long coming from oppositedirection. If the speed of the first trainis 30 kmph, the speed of the secondtrain is
Answer» Let speed of the other train = S m /sec. Speed of the first train = 30 kmph = (30 5)/18 = 8.33 m/sec. Relative speed = (8.33 + S) m/sec. With this relative speed train needs to be covered (150 + 100) m in 10 seconds. So,ST = D(8.33 + S) 10 = 250(8.33 + S) = 25S = 16.67 m/sec Speed = 16.67 m/sec = (16.67 * 18)/5 = 60 kmph.

A train of length 150 metres takes 10seconds to pass over another train 100metres long coming from oppositedirection. If the speed of the first trainis 30 kmph, the speed of the secondtrain is

Answer»

Let speed of the other train = S m /sec.

Speed of the first train = 30 kmph = (30 *5)/18 = 8.33 m/sec.

Relative speed = (8.33 + S) m/sec.

With this relative speed train needs to be covered (150 + 100) m in 10 seconds.

So,ST = D(8.33 + S) * 10 = 250(8.33 + S) = 25S = 16.67 m/sec

Speed = 16.67 m/sec = (16.67 * 18)/5 = 60 kmph.