1. The problem statement, all variables and given/known data Helium gas flows through a well-insulated nozzle at steady state. The temperature and the velocity at the inlet are 550°R and 150 ft/s, respectively. At the exit, the temperature is 400°R and the pressure is 40 lbf/in2. The area of the exit is 0.0085 ft2. Using the ideal gas model with k = 1.67, and neglecting potential energy effects, determine the mass flow rate in lb/s through the nozzle 2. Relevant equations 3. The attempt at a solution My initial response is to use: m' = ρvA but I'm not sure if this is how they want me to find the answer. My professor mentioned: Cp - Cc = R Is this referring to specific heats? My notes also say Cp is constant. What is this referring to? Likewise, what is the significance of the k=1.67?