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Buoyancy calculator

Archimedes’ principle: the upward force on something submerged, and the weight it can hold up before it sinks.

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Buoyant force 980.7 N

How it works

F = ρ × V × g

A submerged object is pushed up by the weight of the fluid it moves aside. One liter of fresh water weighs 1 kg, so a fully submerged 1 L object gets about 9.8 N (1 kg) of lift; in seawater a little more. If the object weighs less than the water it can displace, it floats, and the difference is how much extra load it can carry.

  1. Fluid density × volume × g 1,000 kg/m³ × 0.1 m³ × 9.80665 = 980.7 N
  2. Compare with the object’s mass 100 kg − 30 kg = 70 kg

Printed from rocketcalc.io/physics/buoyancy