Question

What will be the temperature of aircraft flying in air where the stagnation temperature is 288.15K and mach number is 1?

(a) 250.15K

(b) 240.125K

(c) 300K

(d) 270.18K

I had been asked this question by my college professor while I was bunking the class.

My question is from Measurement of Mach Number in section Atmosphere and Air Data Measurement of Aircraft Performance

Answer 1

The correct choice is (b) 240.125K

To explain: The answer is 240.125K. Given T0=288.15K and M=1. By substituting the values in the formula T0=T\(\Big[1+\frac{\gamma-1}{2}M^2\Big]\)

On substituting 288.15=T[1+\(\frac{1.4-1}{2}1^2]\)

T=\(\frac{288.15}{1.2}\)

T=240.125K.