Question

A body has speed V, 2V and 3V in the first 1/3 second 1/3, second 1/3 and the remaining 1/3 of the total ditance respectively its average speed is

Answer 1

$$\begin{array}{l} < V > = \frac{< S >}{< t >} \\ S = S_1 + S_2 + S_3 - \text{Total way} \\ S_1 = \frac{1}{3} Vt \\ S_2 = \frac{1}{3} 2Vt \\ S_3 = \frac{1}{3} 3Vt \\ t = t_1 + t_2 + t_3 - \text{Total time} \\ \text{ANSWER:} \\ \end{array}$$ $$< V > = \frac{\frac{1}{3} Vt + \frac{1}{3} 2Vt + \frac{1}{3} 3Vt}{t} = \frac{\frac{1}{3} 6Vt}{t} = \frac{V}{2}$$