8.5.2. Control Volume in Capillary Problems

Try these first

1. 1.

   Define gauge pressure.

   Hint

   Think about how tire pressures are measured.

2. 2.

   What is hydrostatic pressure?

   Hint

   Consider how deep underwater pressure increases.

3. 3.

   What is the principle of hydrostatic pressure?

   • Pressure increases with surface area.
   • Pressure increases with depth in fluid.
   • Pressure decreases with depth in fluid.

   Hint

   Think about how water pressure is felt as you dive deeper.

4. 4.

   Gauge pressure is measured in relation to which reference?

   • True
   • False

   Hint

   Consider how everyday pressure gauges work.

5. 5.

   Calculate the height to which water rises in a capillary tube of diameter 2mm with a surface tension of 0.072 N/m and a contact angle of 0 degrees. Assume the density of water is 1000 kg/m³.

   Hint

   Remember the formula for capillary rise!

6. 6.

   In a container with two different liquids of different densities, how would you measure the gauge pressure at various heights and explain the results?

   Hint

   Think about the differences in pressure between the two liquids as you measure.