Final answer:
The drainage amount recorded should be a constant value since the drainage system is pressurized continuously because if you open the system, it will lose its controlled pressure.
Step-by-step explanation:
In fluid dynamics, the principle of constant drainage is crucial for maintaining an efficient and controlled drainage system. The term _constant value_ implies that the drainage rate remains uniform under normal operating conditions. This is achieved by ensuring a consistent pressure within the system.
The drainage system is designed to be _pressurized continuously_, and this pressurization is maintained through engineering controls. By keeping the system pressurized, the flow rate of drainage remains stable. Mathematically, this can be expressed as Q = A × v, where Q is the drainage rate, A is the cross-sectional area, and v is the velocity of the fluid. With a constant pressure, both A and v are regulated, ensuring a consistent drainage amount.
Opening the system would lead to a loss of _controlled pressure_, disrupting the equilibrium and causing fluctuations in drainage. This is undesirable, as an uncontrolled drainage system can lead to inefficiencies, potential damage, or compromise the functionality of the system. Therefore, engineers carefully design and maintain drainage systems to operate with a constant pressure, ensuring a reliable and predictable drainage rate. In practical applications, this could involve using pressure relief valves, regulating pumps, or employing other mechanisms to sustain the desired pressure levels in the drainage system.