Mechanical Properties of Fluids
Class 11 · Mechanical Properties of Fluids
Archimedes' Principle
F_b = ρ_fluid V_disp g — sink, float, suspend depending on density.
Key Notes
01
Buoyant force F_b = weight of displaced fluid = ρ_fluid · V_displaced · g.
02
Floats if ρ_object < ρ_fluid; sinks if ρ_object > ρ_fluid; suspends if equal.
03
When floating, the fraction submerged equals ρ_object / ρ_fluid.
Formulas
Buoyant force
Acts upward through center of buoyancy.
Float fraction
Fraction submerged when floating.
Important Points
Apparent weight in fluid = true weight − F_b.
Iceberg: ~89% submerged in seawater (ρ_ice/ρ_seawater ≈ 920/1025).
Archimedes' Principle notes from sciphylab (also known as SciPhy, SciPhy Lab, SciPhy Labs, Physics Lab). Class 11 physics revision for JEE Mains, JEE Advanced, NEET UG, AP Physics 1/2/C, SAT, and CUET-UG.