Archimedes’ Principle

📚 Key Concepts

🔹 Real-Life Example: Ships made of steel float on water despite being denser than water. This is because the ship displaces a volume of water whose weight equals the ship’s weight. Submarines adjust buoyancy by filling or emptying ballast tanks with water, thereby changing their density.

🔹 Archimedes’ Principle: When a body is partially or fully immersed in a fluid, it experiences an upward force equal to the weight of the fluid displaced by it.

🧪 Important Formulas

• 🔸 Mathematical Expression:
  Buoyant Force = Weight of Displaced Fluid
  Fb = ρ(fluid) × V(displaced) × g
  Where:
  • Fb = Buoyant force (N)
  • ρ(fluid) = Density of fluid (kg/m³)
  • V(displaced) = Volume of displaced fluid (m³)
  • g = Acceleration due to gravity (m/s²)

🔹 Applications of Archimedes’ Principle

• 🚢 Ships: Displace water equal to their weight to float
• 🔧 Submarines: Adjust buoyancy with ballast tanks
• 🧪 Hydrometers: Float at different levels to measure fluid density
• 🧊 Icebergs: Approximately 90% underwater and 10% visible

🔍 Advanced: Density and Upthrust Relationship

• Object density < fluid density: Object floats
• Object density = fluid density: Object remains suspended
• Object density > fluid density: Object sinks

🔬 Experiment to Demonstrate Archimedes’ Principle

• Place an object in water and measure the following:
• 1️⃣ Weight of object in air
• 2️⃣ Weight of object in water
• 3️⃣ Difference in weight = Buoyant force = Weight of displaced water