Avg velocity problem

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A train goes around a circle, the first time with an average velocity of 100 km/h. How fast should the train be when going around the circle again a second time, so that the average velocity over the two loops is 200 km/h?

#Physics #Mechanics

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2 Answers

996

Swarna Kamal Dhyawala ·2013-02-28 07:53:30

Let the time taken to go round twice be T1 +T2.
100=D/T1 where D is the circumference of the loop.
What we want is, 200=2D/(T1+T2)
or D= 100(T1 + T2)
D= 100(D/100 + T2)
D=D+100T2
T2=0
which means it should travel with infinite velocity

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Soumyabrata Mondal yap
Upvote·0· Reply ·2013-02-28 08:07:00
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383

Soumyabrata Mondal ·2013-02-28 07:43:16

infinite???

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