Study the Relation between Loss in weight of Solid in Tap water and in Salty water

Our Objective

To establish the relation between the loss in weight of solid when fully immersed (i) tap water; (ii) strongly salty water, with the weight of water displaced by it by taking at least two different solids. 


The Theory

When an object is immersed in fluid, fluid exerts an upward force on it. This force is known as buoyant force. When an object is immersed in fluid it experiences loss in weight and water displaces.

Loss in weight of object = Buoyant force 

Archimede’s Principle 

When a body is immersed fully or partially in a fluid it experiences an upward force that is equal to the weight of the fluid displaced by it. 

Buoyant force (Fb)= ρ* Vf*g 

 Ρ- Density of liquid.

Vf - Volume of liquid displaced

g - Acceleration due to gravity 

Buoyant force is directly proportional to density of the fluid. 

When we immerse a body in fluid its actual weight decreases in fluid due to buoyant force. Corresponding weight in fluid is known as apparent weight  

Apparent weight of an object = Actual weight of an object – Buoyant force 


Learning Outcomes

  • Students understand about buoyant force.
  • Students understand about Archimede’s Principle.
  • Students understand the relationship between density and buoyant force.