With the completion of this lesson, students should be able to:

  • Define pressure and demonstrate pressure exerted by liquid.
  • State and verify Pascal's law with its application.
  • Explain and formulate Archimedes Principle with examples.
  • Explain law of flotation.
  • Solve Numerical problems related to Archimedes Principle



Pressure is defined as force acting per unit area. Its SI unit is Pascal. This note has brief description of pressure.

Pascal's Law

Pascal's law states that "Pressure exerted by liquid in an enclose vessel is transmitted equally". This law is applicable for the gases also. This is the detailed note on pascal's law and its application in hydraulic press.


Density is a physical property of a matter. It can be defined as a ratio of mass per unit volume. This note gives an information about upthrust and density.

Archimedes Principle

We know that due to upthrust, objects tend to lose weight when immersed in liquid. Archimedes principle states that "If an object is partially or completely immersed in the liquid, the weight of liquid displaced by the object is its upthrust". This notes provides an information about Archimedes principle of grade 10.