# Aerodynamics Questions and Answers – Bernoulli’s Equation

This set of Aerodynamics Multiple Choice Questions & Answers (MCQs) focuses on “Bernoulli’s Equation”.

1. The point where the fluid comes to rest is called as ___________
a) Rest point
b) Stagnation point
c) Viscous point
d) Boundary layer point

Explanation: The point at which the flow slows and comes to a halt is known as the circular cylinder. The streamline separates the flow into two sections: upper and lower flow. When the flow cannot enter an object, it must come to a halt at a place known as a stagnation point.

2. Stagnation pressure or the total pressure is the sum of _________
a) Kinetic and potential energy
b) Static and dynamic pressure
c) Kinetic energy +potential energy +gravity
d) Cannot be determined

Explanation: The total pressure or stagnation pressure is the sum of static and dynamic pressure. Let p0 be the total pressure, ps be the static pressure and pd be the dynamic pressure.
Therefore, p0 = ps + pd.

3. The dynamic pressure is given by ______
a) 0.5ρ*V2
b) ρ* V2
c) 3*V2
d) 5ρ* V2

Explanation: The dynamic pressure is not a pressure at all. It merely justifies the pressure drop caused by the increased velocity. It simply states that the pressure falls when the density is half and the velocity is squared.

4. The coefficient of pressure at stagnation point is ___________
a) 0
b) 0.5
c) 1
d) 2

Explanation: The relative pressure at each and every point in a flow field is described by the coefficient of pressure, which is a dimensionally less quantity. Its highest value is at the pressure distribution, and it can vary from point to point in a flow field.

5. The pressure for an ideal gas can be given by ____________
a) pV=nRT
b) p=RT
c) pV=T
d) p=VT

Explanation: Because molecules in an ideal gas have no volume, they do not interact with one another. Pressure is directly proportional to temperature and inversely proportional to volume for a given temperature.

6. Bernoulli’s equation can be directly applied to viscous flow.
a) True
b) False

Explanation: Because the motion of the fluid particle in viscous fluid is continuous, the Bernoulli’s equation cannot be simply applied to it. As a result, we must convert the viscous flow into a Navier-Stoke equation before applying Bernoulli’s equation.

7. Bernoulli’s equation can be applied to compressible flow at which of the following matches the number?
a) mach number less than 1
b) mach number equal to 1
c) higher mach numbers
d) does not depends on mach number

Explanation: According to Bernoulli’s principle, increased velocity lowers pressure, resulting in a higher lift. If the number of matches grows, the pressure gradually reduces resulting in an increase in lift.

8. Bernoulli’s principle is derived from which of the following?
a) Conservation of mass
b) Conservation of energy
c) Newton’s law of motion
d) Conservation of momentum

Explanation: It states that at all sites in a flow field, the sum of all kinds of energy in flow is the same. Kinetic energy, potential energy, and internal energy are all examples of energy.

9. An increase in the speed of the flow leads to an increase in kinetic energy and dynamic pressure.
a) True
b) False

Explanation: The kinetic energy and dynamic pressure of the flow rise as the flow speed increases (0.5*V2). The static pressure declines with the drop in potential energy and internal energy as the dynamic pressure increases, i.e. the density is half and the velocity is squared.

10. The relation between pressure and velocity in an inviscid, incompressible flow is given by __________
a) p = constant
b) p + 0.5ρ*V2 = constant
c) 0.5ρ*V2 = 0
d) p + 0.5ρ*V2 = 0

Explanation: Bernoulli’s equation, p+0.5*V2 = constant, can be used to describe the relationship between pressure and velocity. In the preceding equation, p represents pressure and V represents velocity, implying that as pressure rises, velocity falls, and vice versa.

11. The aircraft fly based on which principle _________
a) Newton’s third law
b) Conservation of mass
c) Bernoulli’s principle
d) Gravity

Explanation: Bernoulli’s principle governs the flight of aircraft. The pressure drops as the air speed rises, resulting in a high lift generation. Pressure is inversely proportional to velocity according to this theory.

12. Bernoulli’s equation is applicable only for _______
a) Irrotational flow
b) Viscous flow
c) Inviscid, incompressible flow
d) Compressible flow

Explanation: Bernoulli’s equation only applies to free surface and incompressible flow because inviscid flow has no viscosity and thus no viscous forces acting on the body, while incompressible flow has a constant density. Many fluid difficulties are alleviated by the oscillatory and incompressible flow.

Bernoulli’s equation in its simplest form can be summarized up in the following memorable word equation: Total pressure equals static pressure plus dynamic pressure. Every location in a constantly flowing fluid has its own static pressure p and dynamic pressure q, regardless of the fluid speed at that place. Bernoulli’s equation formula is a relationship between a fluid in a container’s pressure, kinetic energy, and gravitational potential energy. Bernoulli’s principle is denoted by the formula p + frac12 v2 + gh =constant. The pressure exerted by the fluid is denoted by p.