The sum of the static pressure and dynamic pressure at a point in a fluid flow is called the ________.
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- kinematic pressure
- vacuum pressure
- stagnation pressure
- kinetic pressure
The Correct Option is C
Solution and Explanation
The stagnation pressure is the sum of the static pressure and dynamic pressure at a point in a fluid flow. It represents the pressure a fluid would reach if it were brought to rest isentropically (without heat exchange or dissipation).
Step 1: Definition of static and dynamic pressure.
Static pressure is the pressure exerted by a fluid at rest, while dynamic pressure is associated with the velocity of the fluid flow. The total pressure at a point in the flow is the sum of these two pressures.
Step 2: Analyze each option.
(A) Incorrect. Kinematic pressure is not a term used to describe the sum of static and dynamic pressures.
(B) Incorrect. Vacuum pressure refers to pressures lower than atmospheric pressure, not the sum of static and dynamic pressures.
(C) Correct. Stagnation pressure is the sum of static pressure and dynamic pressure.
(D) Incorrect. Kinetic pressure refers to pressure related to the motion of the fluid, but not specifically the sum of static and dynamic pressures.
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