Question

Consider the control volume form of the basic laws. For the conservation of mass form for a control volume with mass flow into and out of the control volume, the mass in the control volume is: a)- of a known magnitude. b)- always the same c)-dependent on the mass flows in and out d)- none of the above

Answer 1

Answer:

C) Dependent on the mass flows in and out.

Explanation:

Lets take control volume(CV)

Take

          $m_i$ =inlet mass flow rate

          $m_e$ =exit mass flow rate

If we take unsteady flow process then inlet mass can not be equal to exit mass.Some mass can store if inlet mass flow rate is high and exit mass flow rate  is low.

So mass of control volume

    $m_{cv}=m_i-m_e$.

so above we can say that mass of control volume dependent on inlet and exit mass.