Question

What are the limiting conditions for Newtonian theory?

(a) M∞ → ∞

(b) γ → ∞

(c) M∞ → ∞, γ → 1

(d) M∞ → 1, γ → ∞

I had been asked this question during a job interview.

Asked question is from Newtonian Theory topic in division Numerical Techniques for Nonlinear Supersonic Flow, Elements of Hypersonic Flow, Couette and Poiseuille Flow of Aerodynamics

Answer 1

The correct option is (c) M∞ → ∞, γ → 1

To elaborate: Newtonian theory is applicable only under certain limitations. The first being the Mach number tends to infinity as we are talking about hypersonic flows and γ tends to 1. Only under these conditions are the results accurate.