Question

A train covers half of its journey with a speed of 30 m/s and other half with speed of 40 m/s. Calculate it's average speed for the entire journey?​

Answer 1

Explanation:

let d be the distance of journey

now at speed of 30 m/s

it covers d/2 m in time T1

so 30 = d/2T1

T1 =d/60

now it covers at 40 m/s in T2

similarly T2=d/80

total time =T1+T2= d/60+d/80

= 14d/48

= 7d/24

total distance =d

average speed = d/7d ×24

=24/7 m/s

Answer 2

Answer:see the photo.If cannot understand then ask me.

Explanation: