Buoyancy Calculator (Archimedes)
Calculate buoyant force on a submerged object and whether it floats or sinks.
Step-by-step working
- F_b = ρ_fluid g V = 1000 × 9.80665 × 0.01 = 98.0665 N
- W = m g = 78.4532 N
Mathematical Formula
Overview & Explanation
A fluid pushes up with a force equal to the weight of fluid displaced.
How It Works
- Compute displaced fluid weight.
- Compare with object weight.
Practical Applications
- Boat and float design.
Example 1: 10 L, 8 kg in fresh water
Floats.
Inputs
Fluid density (kg/m³): 1000 · Submerged volume (m³): 0.01 · Object mass (kg): 8
Step 1
F_b = ρ_fluid g V = 1000 × 9.80665 × 0.01 = 98.0665 N
Step 2
W = m g = 78.4532 N
Buoyant force
Result
Example 2: 1 L steel (7.85 kg) in sea water
Sinks.
Inputs
Fluid density (kg/m³): 1025 · Submerged volume (m³): 0.001 · Object mass (kg): 7.85
Step 1
F_b = ρ_fluid g V = 1025 × 9.80665 × 0.001 = 10.0518 N
Step 2
W = m g = 76.9822 N
Buoyant force
Result
How it's calculated & sources
F_b = ρ_fluid g V; compare with weight m g.
Frequently Asked Questions
Why does steel float as a ship?
Partially submerged?
Air?
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