7TH GRADE · MASS AND DENSITY
Volume and density of matter
Determination of density and calculation of mass or volume.
The entire theory of the lesson is collected here; you can read it without an account. In interactive mode, the same theory appears as cards, followed by questions. with checking the answer and task, and progress is saved.
Basic Concepts
Volume
A physical quantity showing the portion of space occupied by a body or substance.
The volume of a rectangular bar is determined by its dimensions, and the volume of a body of complex shape is determined by the displaced liquid.
Density table
A lookup table relates a substance to its density at a specified temperature and condition.
Before comparison with the table, convert mass and volume into agreed units and take into account the state of aggregation of the substance.
Density
A physical quantity equal to the mass of a unit volume of a homogeneous substance.
Bodies made of aluminum and steel of the same volume have different masses because the densities of the materials differ.
Physical quantities
Volume
The volume of the body used in calculating density.
Unit: cubic meter ·
Density
The mass of a homogeneous substance per unit volume.
Unit: kilogram per cubic meter ·
Lesson formulas
Density of matter
Density is equal to the mass of a homogeneous body divided by its volume.
Mass by density
Mass is found by multiplying the density of a substance by the volume of the body.
Volume by density
Volume is found by dividing the mass of a body by the density of its substance.
Related formulas
The same formulas in the reference, with symbols and units.
Tasks on the topic
Statements, answer options and the walkthrough.