Question

A boy goes from A to B with a velocity of 20 m/min and comes back from B to A with a velocity of 30 m/min. The average velocity of the boy during the whole journey is

(a) 24 m/min

(b) 25 m/s

(c) Zero

(d) 20 m/min

Answer 1

Answer:

24 m/min

Explanation:

Given:-

• A boy goes from A to B with a velocity of 20 m/min and comes back from B to A with a velocity of 30 m/min

To Find:-

• The average velocity of the boy during the whole journey

Solution:-

We let 60 m as distance the LCM of 20 and 30 is 60

So,

1st time taken which going = Distance/Speed = 60/20 = 3 min

2nd time taken on return = 60/30 = 2 min

Average speed = Total distance/Total time taken

→60+60/2+3

→120/5

→24 m/min

[Option (a) supports the answer]

Answer 2

Answer:

0

Explanation:

vav = displacement÷time

since the object moves from a to b and comes back again to a so the displacement is 0. if. displacement is 0 then the average velocity is also 0. plz don't confuse between speed and velocity