For the normal shock that occurs in front of the Pitot tube in Example 3.7, calculate the entropy change across the shock.

Data From Example 3.7:

Consider a point in a supersonic flow where the static pressure is \(0.4 \mathrm{~atm}\). When a Pitot tube is inserted in the flow at this point, the pressure measured by the Pitot tube is \(3 \mathrm{~atm}\). Calculate the Mach number at this point.