For low-speed (nearly incompressible) gas flow, the stagnation pressure can be computed from Bernoulli€™s equation
(a) For higher subsonic speeds, show that the isentropic relation (9.28a) can be expanded in a power series as follows:
(b) Suppose that a Pitot-static tube in air measures the pressure difference p0 €“ p and uses the Bernoulli relation, with stagnation density, to estimate the gas velocity. At what Mach number will the error be 4 percent?

1 Po = p+pv2 4. 2-k Ma* +... 24 Po = p+pV 1+-Ma + 4