Question 72
The number of circular pipes with an inside radius 0.5 cm which will carry the same amount of water as a pipe with an inside radius of 3 cm is
Solution
Radius of small pipes = 0.5 cm and big pipes = 3 cm
=> Number of circular pipes required = $$\frac{\pi R^2}{\pi r^2}$$
= $$\frac{3^2}{0.5^2}=\frac{9}{0.25}$$
= $$9\times\frac{4}{1}=36$$
=> Ans - (D)
