4.1.1. Inflow and Outflow

Try these first

1. 1.

   What does the mass conservation principle state?

   Hint

   Think about what happens in a closed system.

2. 2.

   Define inflow in fluid dynamics.

   Hint

   Consider incoming water in a pipe.

3. 3.

   What is the state of mass conservation?

   • Mass can be created
   • Mass can be destroyed
   • Mass is conserved in a closed system

   Hint

   Think about a water bottle with no leaks.

4. 4.

   In a steady flow, fluid properties at fixed points change over time.

   • True
   • False

   Hint

   Review the definition of 'steady flow'.

5. 5.

   A horizontal jet of water strikes a vertical plate at 5m/s with an area of 0.05 m². Calculate the force required to keep the plate stationary if the water has a density of 1000 kg/m³.

   Hint

   Use the density and velocity to find the momentum.

6. 6.

   If a spacecraft is decelerating using a jet that discharges at 100 kg/s with a jet velocity of 1500 m/s, calculate the thrust generated given the original speed was 600 m/s.

   Hint

   Use the formula for thrust based on mass flow rate and jet speed.