From input to output a throttle has which of the following c

From input to output a throttle has which of the following characteristics:

A.) constant mass flow

B.) constant pressure

C.) constant phase

D.) constant temperature

Solution

In throttle enthalpy is 0 so woek done is also 0 as h= u+pv ...in throttle pressure ia increase accordingly volume will decrease so mass flow rate will be change ..so only constant phase is feasible ao answer is C