Density Calculator
Inputs
Enter Mass and Volume to calculate Density.
What is Density?
Density (ρ) is a measure of how much mass is contained in a given volume. It essentially describes how compact or "heavy for its size" a substance is.
A rock is denser than a piece of styrofoam of the same size because it has more mass packed into the same volume.
The Density Formula
The standard formula for density is:
ρ = m / V- ρ (rho) = Density
- m = Mass
- V = Volume
Sink or Float?
Density determines whether an object will sink or float in a fluid. Water has a density of approximately 1000 kg/m³ (or 1 g/cm³).
- If an object is less dense than water (e.g., oil, wood), it will float.
- If an object is more dense than water (e.g., rock, iron), it will sink.
Examples
Example 1: Gold Bar
A gold bar has a mass of 19,300 kg and a volume of 1 m³.
- Mass (m) = 19,300 kg
- Volume (V) = 1 m³
- Density = 19,300 / 1 = 19,300 kg/m³ (Standard density of pure gold)
Example 2: Cooking Oil
500 grams of oil occupies 550 cubic centimeters.
- Mass (m) = 500 g
- Volume (V) = 550 cm³
- Density = 500 / 550 ≈ 0.91 g/cm³ (Less than water, so it floats!)
Frequently Asked Questions
Does density change with temperature?
Yes! Most substances expand when heated (volume increases), so their density decreases. Cold air is denser than warm air, which is why hot air rises.
What is specific gravity?
Specific gravity is the ratio of a substance's density to the density of water. It is a unitless number.
How do I measure the volume of an irregular shape?
You can use the water displacement method (Archimedes' Principle). Submerge the object in water and measure how much the water level rises. That's the volume!