Archimedes’ Principle

Archimedes Principle states that when a body is wholly or partially immersed in a fluid it experiences an upthrust equal to the weight of the fluid displaced.



Buoyant force
Buoyant force is an upward force exerted by a fluid on an object immersed in it.

Principle of Floatation:
•Displaced volume of fluid = volume of the object that immerse in the fluid.
•If weight of the object > upthrust, the object will sink into the fluid.
•If weight of the object = upthrust, the object is in balance and therefore float on the surface of the fluid.


Density of Object < Density of water: Partially Immerse





Upthrust = Weight

Upthrust, F = ρliquidVliquidg
Weight, W = mg =ρobjectVobjectg






Density of Object < Density of water: Fully Immerse





F = T + W

F = Upthrust
T = Tension of the string
W = Weight

Upthrust, F = ρliquidVliquidg
Weight, W = mg =ρobjectVobjectg