8.6.1. Measurement of Atmospheric Pressure

Try these first

1. 1.

   What is the definition of pressure?

   Hint

   Think about how pressure relates to forces and areas.

2. 2.

   What is gauge pressure?

   Hint

   Consider how we measure pressure in everyday applications.

3. 3.

   What principle does Pascal's law express?

   • Pressure is the same everywhere
   • Pressure changes with depth
   • Pressure is transmitted undiminished

   Hint

   Consider how pressure behaves within a confined space.

4. 4.

   True or False: Gauge pressure is always measured below atmospheric pressure.

   • True
   • False

   Hint

   Recall the definitions of gauge and vacuum pressures.

5. 5.

   A mercury barometer shows a height of 760 mm. Calculate the atmospheric pressure in pascals.

   Hint

   Use the known parameters of density and gravity to find the force per unit area.

6. 6.

   In a sealed container, gauge pressure is measured to be 300 kPa. What is the absolute pressure if the local atmospheric pressure is 100 kPa?

   Hint

   Remember the relationship between gauge and absolute pressures!