The pump is operating so that the axial velocity at the inlet to the first stator is 10 m/s . The tangential velocities are zero before the first stator, Vt=−1.2m/s after the first stator, Vt = 1.5 m/s after the rotor, and zero after the second stator. What torque does the fluid exert on the pump's stators? The diameters are d1 = 12 cm and d2 = 16 cm and the fluid density is rho = 1000 kg/m3 .

An inventor claims to have developed a reversed heat engine (ie. a heat pump) which is able to deliver 10 kj heat into the room at 20°c from outside ambient temperature of -10°c by consuming only 2 kj electricity in winter. this claim is a)-impossible b)-possible only if the heat pump is ideal c)-practically possible d)-unable to be assessed as it depends on the working fluid used in the heat pump.