What is a wave diagram?

Plot of wave motion between x and t

Diagram of shock creation inside shock tube

Plot of wave motion between t and x

Plot of reflected wave motion between t and x

Correct Answer : Plot of wave motion between t and x

Explanation : When unsteady wave motion i.e. moving shock wave is studied, wave diagram is often constructed. It is a sketch of the wave diagram plot on a graph with x – axis representing distance and y – axis representing the time. The diagram shows where the incident, reflected shock occurs after applying the boundary conditions.

Recently Updated in Aerodynamics Questions

What is the slope for C_– characteristic line?

u + a

u – a

u/a

Correct Answer : Option (C) : u – a

Explaination : At a point (x,y) in an x – y plane there exists paths through this point known as C₊ and C_– characteristic lines. They represent the path of sound waves which are left and right running. The slope for a C_– characteristic line is given by u – a and for C₊ characteristic is u + a.

What is the region in a finite wave called where density increases?

Linearized region

Expansion region

Propagating region

Compression region

Correct Answer : Option (D) : Compression region

Explanation : The density of the finite wave varies along the distance of its propagation. The region where the density increases is known as the finite compression region, and the portion where the density decreases is known as the finite expansion region.

Which of these is not a property of finite wave?

Wave shape changes

Linear equations are used to govern the flow variables

The perturbations are large

Wave propagates with added local speed and speed of sound

Correct Answer : Option (B) : Linear equations are used to govern the flow variables

Explanation : Finite waves unlike the sound waves have high perturbation of density, velocity, temperature etc. They are known to propagate at speed which is an addition of local speed of mass velocity and speed of sound. The shape of the finite wave does not remain constant like the sound waves and the flow variables are governed by the nonlinear equations.