A small solid-fuel rocket motor is fired on a test stand. The combustion chamber is circular, with 130 mm diameter. Fuel, of density 1530 kg/m3, burns uniformly at the rate of 14.5 mm/s. Measurements show that the exhaust gases leave the rocket at ambient pressure, at a speed of 2400 m/s. The absolute pressure and temperature in the combustion chamber are 8.5 MPa and 3600 K, respectively. Treat the combustion products as an ideal gas with molecular mass of 25.5. Evaluate the rate of change of mass and of linear momentum within the rocket motor. Express the rate of change of linear momentum within the motor as a percentage of the motor thrust.
