# Physics

a train travels the first 30 km of 120 km track with a uniform speed of 30km/h.What should be the speed of train to cover the remaining distance of the track so that its average speed is 60km/h for the entire trip

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1. Total distance = 120 km
For an average of 60km/h,
total time available = 120/60=2 hours

Distance left = 120-30=90 km
Time left = 2-1 = 1 hour

What is the speed need for the remaining distance?

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2. avg speed= distance/totaltime
total time=time1+time2
= 30km/30km/hr + time2

avg speed=60=120/total time
total time=120/60=2h
30km/30km/hr + time2=2 hr
time2=1hr
but speed2=90km/1hr=90 km/hr

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3. a train normally travel at a uniform speed of 24 km per hour

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posted by Sakshi

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