Question

What is the mass of $5{m^3}$ of cement of density $3000kg/{m^3}$?

Answer 1

Hint: We are given the volume and density of the cement. In order to find out its mass, we know that density is defined as mass per unit volume. Using this formula, we can calculate the mass of the given cement.
Formula used:
The density of a material can be calculated from the mass and the volume of the object by the following formula.
$\rho = \dfrac{m}{V}$

Complete step by step answer:
We are given a certain amount of cement. Its density is given as
$\rho = 3000kg/{m^3}$
We are also given the volume of the cement. Its value is given as
$V = 5{m^3}$
It is required to find out the mass of the cement for these given values of volume and density. We know that density of an object is defined as the mass of the object per unit volume of the object. The formula is given as
$\rho = \dfrac{m}{V}$
Here $\rho $ is the density of the object, m is the mass of the object while V represents the volume of the object.
Therefore, we can calculate the mass of the object by the following formula.
$m = \rho V$
Now we can insert the known values of the density and the volume of the given cement. It can be done in the following way.
$m = 3000kg/{m^3} \times 5{m^3} = 15000kg$
This is the required value of the mass of the given cement.

Note:
The mass and the volume of an object are the extensive properties of a system which means that these quantities depend on the size of the given system. On the other hand, density is an intensive quantity, which means that the density of a system does not depend on the size of a system. The density of an object remains the same whether we have 10kg of that object or 100kg.