======Archimedes’ Principle======


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**Alternative titles:** Buoyant Force and Displacement
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====Summary====                   
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====Procedure====  
  - Fill a large beaker (about 2 liters) with water.  
  - Attach cotton loops to two equal-mass objects (e.g., 1 kg of aluminum and 1 kg of brass).  
  - Suspend each mass from a spring balance and record its weight in air.  
  - Slowly immerse the aluminum mass in the beaker of water and observe the decrease in the reading on the spring balance.  
  - Repeat with the brass mass and compare the apparent weight reduction.  
  - Note that the less dense aluminum displaces more water and thus experiences a greater buoyant force.



====Links==== 
Conceptual Physics: Demo of Archimedes' principle - Marshall Ellenstein: 
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Archimedes Principle demonstration - KClassScienceChannel: 
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📄 Archimedes' Principle - Harvard Natural Sciences Lecture Demonstrations: [[https://sciencedemonstrations.fas.harvard.edu/presentations/archimedes-principle]]\\


====Variations====
  * Try objects of different materials but equal volume to compare differences in buoyant force.  
  * Repeat the experiment in liquids of different densities (e.g., saltwater, oil) to show how buoyancy depends on the fluid.  
  * Use irregular objects (like a stone or crown replica) to illustrate Archimedes’ original problem.



====Safety Precautions====
  * Handle heavy masses carefully to avoid dropping them.  
  * Ensure the beaker is on a stable surface to prevent spills.  
  * Dry equipment after use to prevent slipping hazards.




====Questions to Consider====
  * Why does the aluminum mass experience a greater buoyant force than the brass mass? (Because aluminum has lower density, so it displaces more water when submerged.)  
  * How does Archimedes’ principle explain why ships made of steel can float? (Although steel is dense, the overall structure displaces enough water to balance its weight.)  
  * How did Archimedes use this principle to test the king’s crown? (By comparing the crown’s displacement in water to that of pure gold of the same weight.)