Question

A train covers half of its journey with a speed of 30 m/s and the other half with a speed of 40 m/s.

Calculate the average speed of the train during the whole journey.​

Answer 1

s = total distance. t1 and t2 are durations for covering half total distance.

s/2 = 30 * t1

s/2 = 40 * t2

So total time duration = t1+t2 = s*[1/60 + 1/80]

Avg velocity = s/(t1+t2)=

240/7 m/s= 34.28 m/s

Answer 2

Answer:35 m/s

Explanation:This is because average speed is the sum of speeds given divided by the number of speeds given. In this case, 30 and 40 m/s are the two speeds given so, (30+40)/2 = 35 m/s.