Two streams of air enter a control volume: stream 1 enters at a rate of 0.05 kg / s at 300 kPa and 380 K, while stream 2 enters
at 400 kPa and 300 K. Stream 3 leaves the control volume at 150 kPa and 270 K. The control volume does 3 kW of work on the surroundings while losing 5 kW of heat. Find the mass flow rate of stream 2. Neglect changes in kinetic and potential energy.
1 answer:
Answer:
0.08kg/s
Explanation:
For this problem you must use 2 equations, the first is the continuity equation that indicates that all the mass flows that enter is equal to those that leave the system, there you have the first equation.
The second equation is obtained using the first law of thermodynamics that indicates that all the energies that enter a system are the same that come out, you must take into account the heat flows, work and mass flows of each state, as well as their enthalpies found with the temperature.
finally you use the two previous equations to make a system and find the mass flows
I attached procedure
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Answer:
option (c) is the correct answer which is zero acceleration.
Explanation:
It is given in the question that the velocity is constant.
Now,
the options are provided in relation to the acceleration.
We know,
acceleration is rate of change of velocity per unit time i.e
acceleration =
since, the change in velocity is given to be zero,
thus, dV/dt = 0
hence,
acceleration = 0
therefore, option (c) is the correct answer which is zero acceleration.