# Pipes and Cisterns Formulas, Shortcut Tricks

Pipes and Cisterns Shortcut Tricks - Page 2
Pipes and Cisterns Important Questions - Page 3
Pipes and Cisterns Video Tutorials - Page 4

## Pipes and Cisterns Formulas

BASIC CONDITION AND FORMULAS FOR PIPES And CISTERNS

• Inlet : A pipe connected with a tank or a cistern or a reservoir, that fills it, is known as an inlet.
Outlet: A pipe connected with a tank or cistern or reservoir, emptying it, is known as an outlet.
• If a pipe can fill a tank in x hours, then: part fill in 1 hour = $\frac{1}{x}$
• If a pipe can empty a tank in y hours, then: part emptied in 1 hour = $\frac{1}{y}$
• If a pipe can fill a tank in x hours and another pipe can empty the full tank in y hours (where y > x), then on opening both the pipes, then the net part filled in 1 hour = $(\frac{1}{x}-\frac{1}{y})$
• If a pipe can fill a tank in x hours and another pipe can empty the full tank in y hours (where y > x), then on opening both the pipes, then the net part emptied in 1 hour = (1 - 1 )
• Time for filling , (Filling pipe is bigger in size.) , F = $\frac{e\times f}{e-f}$
• Time for emptying , (emptying pipe is bigger in size.) , E = $\frac{f\times e}{f-e}$
• Pipes 'A' & 'B' can fill a tank in f1hrs & f2hrs respectively.Another pipe 'C' can empty the full tank in 'e'hrs.If the three pipes are opened simultaneously then the tank is filled in. F = $\left[\frac{L}{\frac{L}{F_{1}}+\frac{L}{F_{2}}-\frac{L}{e}}\right ]$
• Two taps 'A' & 'B' can fill a tank in 't1' & 't2' hrs respectively.Another pipe 'C' can empty the full tank in 'e'hrs.If the tank is full & all the three pipes are opened simultaneously . Then the tank will be emptied in, E = $\left [ \frac{L}{\frac{L}{e}-\frac{L}{F_{1}}-\frac{L}{F_{2}}} \right ]$
• Capacity of the tank is , F = $\left(\frac{f\times e}{e-f}\right)$