A train 125 m long passes a man, running at 5 km/hr in the same direction in which the train is going, in 10 seconds. What is the speed of the train ?
let speed of train be X m/s so, {(X-5)*9/3600}=125/1000 =>X-5 =1(25/9)*(18/5) =>X-5 =50 =>X =55 km/hr
Speed of train=s1=x kmph speedof man=s2=5kmph Relative speed =s=(s1-s2)=(x-5)kmph Time=10sec=10/3600hr length of train=d=125m=125/1000km d=t*s 125/1000=(10/3600)*(x-5) x=50kmph Ans:speed of the train is 50kmph
Speed of the train relative to man = 125/10 m/sec =>25/2 m/sec =>(25/2)*18/5 => 45 km/hr. Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr so x - 5 = 45 x = 50 km/hr speed of train = 50 km/hr
I believe the correct answer is 50km/hr, though I found it in a much more circuitous way than the people below.
A train 220 m long is running with a speed of 60 kmph. In what time will it pass a man who is running at 6 kmph in the direction opposite to that in which the train is going?
How many seconds will a 468 m long train take to cross a man driving his motor bike at a speed of 39 km/hr in a direction of the moving train if the speed of the train is 120 km/hr?