Archimedes' Principle Calculator

Calculate buoyant force, object density, and floating behavior using Archimedes' principle

Archimedes' Principle Calculator

True mass of the object in air

Volume of the immersed object

Select the fluid the object is immersed in

Density of the fluid at standard conditions

Standard gravity: 9.807 m/s² (Earth surface)

Calculation Results

Buoyant Force

0.00 N
Upward force from fluid

Object Density

0.0 kg/m³
Object material density
49.04 N
True Weight
49.04 N
Apparent Weight
0.000000 m3
Volume Displaced

Floating Behavior

🔽 Object will SINK
Object weight is greater than buoyant force

Archimedes' Principle: F_B = V × ρ_fluid × g

Where: F_B = Buoyant force, V = Volume displaced, ρ = Fluid density, g = Gravity

Mass displaced: 0.000 kg

Physics Analysis

Example Calculation - Aluminum Block in Water

Given Parameters

Object: Aluminum block

Mass: 1,000,000 kg (1000 metric tons)

Aluminum density: 2,700 kg/m³

Fluid: Water (density = 1,000 kg/m³)

Calculation Steps

Step 1: Calculate volume of aluminum block

V = mass / density = 1,000,000 kg ÷ 2,700 kg/m³ = 370.4 m³

Step 2: Calculate buoyant force

F_B = V × ρ_water × g = 370.4 m³ × 1,000 kg/m³ × 9.807 m/s²

Result: F_B = 3.63 × 10⁶ N (3.63 MN)

Conclusion: Block will sink (density ratio: 2.7)

Common Fluid Densities

Water (20°C)1,000 kg/m³
Seawater1,025 kg/m³
Mercury13,534 kg/m³
Ethanol789 kg/m³
Crude Oil870 kg/m³

Applications

🚢

Ship Design: Determining displacement and stability

🎈

Hot Air Balloons: Calculating lift force

🔬

Hydrometers: Measuring fluid density

💎

Geology: Determining mineral density

🏊

Swimming: Understanding buoyancy in humans

Understanding Archimedes' Principle

What is Archimedes' Principle?

Archimedes' principle states that when an object is partially or wholly immersed in a fluid, the buoyant force acting on it is equal to the weight of the fluid displaced by the object. This principle explains why some objects float while others sink.

The Physics Behind Buoyancy

  • Pressure increases with depth in fluids
  • Higher pressure at bottom creates net upward force
  • Buoyant force depends on fluid density, not object density
  • Volume of displaced fluid equals immersed volume

Archimedes' Principle Formula

F_B = V × ρ_fluid × g

  • F_B: Buoyant force (N)
  • V: Volume of displaced fluid (m³)
  • ρ_fluid: Density of fluid (kg/m³)
  • g: Acceleration due to gravity (m/s²)

Floating vs Sinking

Object floats if: ρ_object < ρ_fluid

  • Float: Buoyant force ≥ Object weight
  • Sink: Buoyant force < Object weight
  • Neutral: Buoyant force = Object weight

Historical Note: Discovered by Archimedes of Syracuse (c. 287-212 BCE)

Practical Applications and Examples

Ship Design

Displacement Principle

Ships are designed so the weight of water they displace equals their total weight, allowing massive steel vessels to float.

Density Measurement

Hydrostatic Weighing

By measuring an object's weight in air and in water, its density can be calculated using Archimedes' principle.