Pressure

• $P = \frac{F_\perp}{A}$.
• Unit: $N/m^2 = Pa$.

Buoyancy and Archimedes' Principle

• Archimedes' Principle: buoyant force equals to the weight of the fluid displaced.
• Density of water: $\rho_{water}=1g/cm^3 = 1000kg/m^3$.
• The amount of fluid dispaced is shown on the right.
• The more fluid the block displaces, the stronger is the buoyant force.
• The block displaces exactly $10N$ of water when completely submerged.
• To find the volume of the block: $\rho_{water}V g = 10N \Rightarrow V = \frac{10}{(9.8)(1000)} = 1.02\times 10^{-3}m^3$.