Question

a body has speed V,2V and 3Vin first 1/3 of distance S,second 1/3 of S and third 1/3 of S respectively. what is the average speed

Answer 1

first take out the distance and then take out average speed with total speed/total time

Answer 2

Answer:

The average speed is 1.6 V

Explanation:

The speed of the body in the first 1/3rd  of distance S, second 1/3rd  of S and third 1/3rd  of S are respectively V, 2V and 3V.

We have to calculate the average speed. The formula for the calculation of average speed = Total distance/Total time taken

The sum of all the speeds = d/3 + d/3 + d/3 = d

Total time taken = $\frac{d / 3}{V}+\frac{d / 3}{2 V}+\frac{d / 3}{3 V}=\frac{d}{3 V}(11 / 6)=\frac{11 d}{18 V}$

Average speed = $\frac{d}{11 d / 18 V}=\frac{18}{11} V=1.6 V$