Density

What is Density?

Density of a substance is the ratio of mass to a volume of a substance.

OR

Density is mass per unit volume of a substance.

Density is represented by the Greek symbol rho, \( \scriptsize \rho \)

⇒ \( \scriptsize Density, \: \rho = \normalsize \frac {mass}{volume} \)

= \( \frac {kilogramme}{m^3} \\ = \scriptsize kgm^{-3}\)

Its unit is kgm^-3 .

Different materials have different densities as shown;

Determination of Density of a Solid:

(i) Regular Shaped Object: The mass of a regular object is measured with a chemical balance or beam balance and its volume measured by metre rule, vernier calliper or micrometre screw gauge, depending on the shape of the body.

The density is then calculated by applying the formula:

Density = \( \frac {mass}{volume}\)

\( \scriptsize \rho = \normalsize \frac {m}{v}\)

(ii) Irregular Shaped Object: The volume of the object is determined by displacement method using Eureka can.

The volume of water displaced by suspending the object in the water is equal to the volume of the object.

The Formula for density (ρ), \( \frac {mass}{volume}\), is used to determine the density