Physics

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Immersed Weight Calculator.

Calculate apparent weight after buoyancy in a fluid.

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Apparent weight: 78.4532

Apparent weight

0.000000
Buoyant force: 19.6133

Buoyant force

0.000000

Educational SI models with assumptions stated in each description; verify engineering decisions independently.

Use Cases

Physics homework and experiments

Quickly verify apparent weight calculations for objects submerged in different fluids, aiding in understanding buoyancy principles.

Example: Calculate the apparent weight of a 2 kg object with 0.001 m³ volume in water (density 1000 kg/m³).

Engineering and design

Determine the effective weight of submerged components for designing floats, submarines, or underwater structures.

Example: Estimate the load on a cable lifting a submerged concrete block.

Frequently Asked Questions

What is apparent weight and how is it calculated?
Apparent weight is the weight of an object as measured when submerged in a fluid, accounting for buoyancy. It is calculated as (object mass × gravity) - (fluid density × displaced volume × gravity). This calculator uses your inputs for object mass, displaced volume, fluid density, and gravity to compute the immersed weight.
Why do I need to input displaced volume and fluid density?
Displaced volume and fluid density determine the buoyant force acting on the object. The buoyant force equals fluid density × displaced volume × gravity. Subtracting this from the object's actual weight gives the apparent weight. These inputs are essential for accurate calculation.
Can this calculator be used for any fluid?
Yes, as long as you know the fluid's density. For example, water has a density of about 1000 kg/m³, while air is about 1.225 kg/m³. Enter the appropriate density for your fluid to get the correct apparent weight.

Tips & Common Mistakes

Tips

  • Ensure the displaced volume is the volume of the object submerged, not the total object volume if partially submerged.
  • Use consistent units: mass in kg, volume in m³, density in kg/m³, and gravity in m/s² for accurate results.
  • For freshwater, use density 1000 kg/m³; for seawater, about 1025 kg/m³; adjust for temperature and salinity.
  • If the apparent weight is negative, the object will float; the calculator still provides the numerical value.

Common Mistakes to Avoid

  • Using the object's total volume instead of the displaced volume when the object is not fully submerged.
  • Forgetting to convert units, such as using liters for volume instead of cubic meters, which leads to incorrect results.
  • Entering fluid density in g/cm³ without converting to kg/m³ (1 g/cm³ = 1000 kg/m³).

Last updated: August 13, 2026