Question

12) A train covers half of its journey with a speed of 30 ms-1 and the other half with a speed of 40 ms Calculate the speed of the train during the whole journey? (1) 34.3 km h-1 (2)33.3 km h-1 h (3) 32.3 km h-1 (4) 36.3 km h-1 ​

Answer 1

Answer:

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:

34.38m/s or 123.768 kilometres per hour

Explanation:

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