15.5.1. Conservation of Mass

Try these first

1. 1.

   What does the conservation of mass state?

   Hint

   Think about a system where mass stays the same.

2. 2.

   Name one type of control volume.

   Hint

   Consider whether the volume stays still or changes shape.

3. 3.

   What does the conservation of mass imply?

   • A. Mass can be created
   • B. Mass can be destroyed
   • C. Mass remains constant
   • D. Mass can change

   Hint

   Think about a closed container.

4. 4.

   The Reynolds transport theorem relates to which aspect of fluid mechanics?

   • A. Pressure only
   • B. Mass flow only
   • C. Energy balance
   • D. All of the above

   Hint

   Consider mass in a defined area.

5. 5.

   A pipeline transports water at 5 m/s with a diameter of 0.1 m. Calculate the mass flow if the water density is 1000 kg/m³.

   Hint

   Use mass flow rate formula: ρAV.

6. 6.

   If a tank has an inflow rate of 3 m³/s and an outflow rate of 2.5 m³/s, determine the change in water volume over 10 seconds.

   Hint

   Look at the difference between inflow and outflow rates.