Calculator Inputs
Example Data Table
| Sample | Mass (g) | Initial Level (mL) | Final Level (mL) | Volume (mL) | Density (g/cm³) |
|---|---|---|---|---|---|
| Aluminum Piece | 54.0 | 30.0 | 50.0 | 20.0 | 2.70 |
| Glass Marble | 15.6 | 20.0 | 26.0 | 6.0 | 2.60 |
| Plastic Block | 18.2 | 45.0 | 63.0 | 18.0 | 1.01 |
| Stone Chip | 32.4 | 10.0 | 22.0 | 12.0 | 2.70 |
| Copper Nugget | 44.8 | 12.0 | 17.0 | 5.0 | 8.96 |
Formula Used
1. Displaced Volume
Object Volume = Final Water Level − Initial Water Level
2. Density
Density = Mass ÷ Object Volume
3. Specific Gravity
Specific Gravity = Object Density ÷ Water Density
4. Volume Uncertainty
Volume Uncertainty = √(Reading Uncertainty² + Reading Uncertainty²)
5. Density Uncertainty
Relative Density Uncertainty = √[(Mass Uncertainty ÷ Mass)² + (Volume Uncertainty ÷ Volume)²]
Absolute Density Uncertainty = Density × Relative Density Uncertainty
6. Percent Error
Percent Error = ((Measured Density − Reference Density) ÷ Reference Density) × 100
mL and cm³ are numerically equal. This calculator converts everything into grams and milliliters before reporting the chosen density unit.
How to Use This Calculator
- Enter a sample name for clear reporting.
- Enter the object mass and choose its unit.
- Enter the balance uncertainty if you want error propagation.
- Record the initial water level before immersion.
- Record the final water level after full immersion.
- Choose the water level unit used in the cylinder.
- Enter a reading uncertainty for the volume scale.
- Select the density unit you want in the answer.
- Optionally enter a reference density for comparison.
- Choose significant figures, then click Calculate Density.
- Review the result, chart, material hint, and comparison values.
- Use the export buttons to save a CSV or PDF summary.
Frequently Asked Questions
1. Why is water displacement useful for density?
It helps measure volume for irregular objects. You do not need to calculate length, width, and height. The displaced water directly reveals the object's volume.
2. Can I use this method for any object?
It works best for solid objects that sink, do not dissolve, and do not absorb much water. Floating or porous samples need extra handling.
3. Why must the final water level be higher?
The object should raise the liquid level after immersion. If the final level is not higher, the readings are incorrect or the object was not fully submerged.
4. Is mL the same as cm³ here?
Yes. One milliliter equals one cubic centimeter. That makes graduated cylinder readings easy to use for density calculations in common laboratory work.
5. What increases accuracy most?
Use a precise balance, read the meniscus carefully, avoid trapped air bubbles, and choose a cylinder size that gives a noticeable water rise.
6. What does specific gravity show?
It compares the sample density with water. A value above 1 suggests the material is denser than water. A value below 1 suggests it is lighter.
7. Why include uncertainty inputs?
Uncertainty shows how precise the measurement is. It helps you judge confidence, compare repeated trials, and report lab results more professionally.
8. What if my object floats?
You can use a sinker or tie the sample below the surface, then correct for the sinker volume. This page does not apply that correction automatically.