The aircraft fly in the atmosphere due to which of the following principle?

Bernoulli's principle

Gravitational force

Archimedes principle

Newton�s law of viscosity

Correct Answer : Bernoulli's principle

Explanation : Bernoulli’s principle states that the sum of all the forms of energy (potential energy, kinetic energy, internal energy) remains constant. Only the weight of the body and the pressure forces act on the body.

Recently Updated in Aerodynamics Questions

The nature of the boundary layer depends on __________

Viscosity

Inertia force

Mach number

Reynold�s number

Correct Answer : Option (D) : Reynold�s number

Explanation : The nature of the boundary layer depends on Reynold’s number which is the ratio of inertial force to viscous force. Depending on the value of Reynold’s number, the boundary layer may be laminar (the flow is continuous) or it may be turbulent ( the flow is discontinuous).

In microscopic view, Circulation is a __________ quantity.

scalar

vector

dimension less

non-measurable

Correct Answer : Option (A) : scalar

Explanation : In a macroscopic view, circulation is a scalar quantity as it is defined as the line integral of velocity field over a closed region. In a microscopic view, circulation is a flux of vorticity, which makes it a vector quantity.

The boundary layer is formed at the ____________

edges of an object

surface of an object

boundary of an object

at a point on an object

Correct Answer : Option (C) : boundary of an object

Explanation : The boundary layer is formed at the boundary of an object. The boundary layer divides the flow into two parts- Viscous and inviscid. The flow inside the boundary layer is highly viscous whereas, the flow outside the boundary is inviscid flow.