14. Introduction to Conservation Principles

Try these first

1. 1.

   What is conservation of mass?

   Hint

   Think about what happens in a closed system.

2. 2.

   Give an example of an extensive property.

   Hint

   Consider properties that change with the amount of substance.

3. 3.

   Which conservation principle states that mass cannot be created or destroyed?

   • Conservation of Momentum
   • Conservation of Energy
   • Conservation of Mass

   Hint

   Consider a closed container.

4. 4.

   True or False: Intensive properties depend on the quantity of material.

   • True
   • False

   Hint

   Think about temperature versus volume.

5. 5.

   A fluid is flowing through a pipe and faces a constriction that reduces the diameter by half. Calculate the change in flow velocity if the flow is incompressible.

   Hint

   Remember that the flow rate must remain constant.

6. 6.

   In a control volume, a fluid is entering with a mass flow rate of 5 kg/s and exiting with 4 kg/s. Calculate the change in mass within the control volume over 10 seconds.

   Hint

   Consider how mass flows in and out of the control volume.