Question

A body travels from A to B speed of 10 m/s & back to A along the same path of speed of 15 m/s . Find its average speed for journey A to B to A.​

Answer 1

Answer:

the average speed is 10m/s + 15m/s divided by 2

Answer 2

Answer:

Average Speed = 12 m/s

Explanation:

Average Speed = Total Distance / Total Time

Here, let the distance be x and time be t

Time = Distance/Speed

Average Speed =

$\frac{2x}{ \frac{x}{15} + \frac{x}{10} } = \frac{2x}{ x( \frac{1}{15} + \frac{1}{10})}$

=

$\frac{2}{ \frac{2 + 3}{30} } = \frac{2}{5} \times 30$

= 2 × 6 = 12 m/s