Question

A farmer connect a pipe of internal diameter $20cm$ from a canal into a cylindrical tank is his field, which is $10m$ in diameter and $2m$ deep. If water through the pipe at the rate of $4km/h$, in how much time will the tank be field.

Answer 1

Volume of cylindrical tank $={\pi r}^{2}h$

$=\frac{22}{7}\times 5\times 5\times 2$

$=\frac{550}{7}{m}^3$

Volume of water coming $=4km/h\times {\pi r}^2$

$=4000\times \frac{22}{7}\times \frac{0.2}{2}\times \frac{0.2}{2}$

$=\frac{3520}{28}{m}^3/hr$

$=\frac{3520}{28\times 60}{m}^3/min$

Time taken $=\frac{550/7}{3520/28\times 60}=\frac{550\times 28\times 60}{3520\times 7}=37.5min$