Elitmus
Exam
Numerical Ability
Time Distance and Speed
A train has a length of 150 meters . it is passing a man who is moving at 2 km/hr in the same direction of the train, in 3 seconds. Find out the speed of the train.
Options
1) 182 km/hr
2) 180 km/hr
3) 152 km/hr
4) 169 km/hr
Read Solution (Total 4)
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- ans : 182 km/hr
reltaive velocity equation is
time(T)=total distance/relative velocity;
let velocity of train is Vt
so here both train and man moving in same direction
so realtive velocity would be (V)=Vt-2
all parameter convert in km and hour
total distance (D)=150/1000 km
total time (T)= 3/60*60 hour
therefore
=>3/60*60 = 150/10008(Vt-2)
after solving above equation ,we get
Vt=182 km/hr
check it, Am i correct - 9 years agoHelpfull: Yes(6) No(0)
- speed of man=2*(5/18)=5/9 m/s
so, 3=150/s-(5/9)
s-(5/9)=50
s=50+(5/9)=500/9 m/s
=(500/9)*(18/5)
=200 km/h is the speed of train - 9 years agoHelpfull: Yes(1) No(3)
- 182 km/hr is the correct answer of this question.
- 9 years agoHelpfull: Yes(0) No(0)
- according to formula [d/(x-x1) = t ]where "d" is the distance, "x "is the speed of train, "x1" is the speed of moving boy (same direction that's why -ve sign concept of relative speed, if the boy moving in the opposite direction put+ve sign instead of -ve), t is the time. put the value in the formula and get the answer.
- 9 years agoHelpfull: Yes(0) No(0)
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