Define pressure. Give its SI unit.
The total force applied per unit area is called pressure.
Mathematically,
Pressure (P) = Force (F) / Area (A)
Its SI unit is pascal (Pa).
State Archimede's principle.
Archimede's principle states that when a body is partially or wholly immersed in a liquid, it experiences an upthrust that is equal to the weight of the liquid displaced by it.