Density

If [tex]25 \, \text{cm}^3[/tex] of a certain material has a mass of 459 grams, calculate the density of this material in [tex]\text{kg}/\text{m}^3[/tex].



Answer :

To calculate the density ([tex]\( \rho \)[/tex]) of a material, we use the formula:

[tex]\[ \rho = \frac{\text{mass}}{\text{volume}} \][/tex]

Given:
- Volume ([tex]\( V \)[/tex]) = [tex]\( 25 \, \text{cm}^3 \)[/tex]
- Mass ([tex]\( m \)[/tex]) = [tex]\( 459 \, \text{g} \)[/tex]

First, we need to convert the mass from grams to kilograms, since the density is to be found in [tex]\( \text{kg/m}^3 \)[/tex].

1 gram (g) = 0.001 kilograms (kg)

Thus, the mass in kilograms is:
[tex]\[ m = 459 \, \text{g} \times 0.001 \, \frac{\text{kg}}{\text{g}} = 0.459 \, \text{kg} \][/tex]

Next, we convert the volume from cubic centimeters ([tex]\( \text{cm}^3 \)[/tex]) to cubic meters ([tex]\( \text{m}^3 \)[/tex]), since we need the density in [tex]\( \text{kg/m}^3 \)[/tex].

1 cubic meter ([tex]\( \text{m}^3 \)[/tex]) = 1,000,000 cubic centimeters ([tex]\( \text{cm}^3 \)[/tex])

Thus, the volume in cubic meters is:
[tex]\[ V = 25 \, \text{cm}^3 \times \frac{1 \, \text{m}^3}{1,000,000 \, \text{cm}^3} = 25 \times 10^{-6} \, \text{m}^3 = 2.5 \times 10^{-5} \, \text{m}^3 \][/tex]

Now, we use the density formula:
[tex]\[ \rho = \frac{m}{V} = \frac{0.459 \, \text{kg}}{2.5 \times 10^{-5} \, \text{m}^3} \][/tex]

Performing the division:
[tex]\[ \rho = \frac{0.459}{2.5 \times 10^{-5}} = 18360 \, \text{kg/m}^3 \][/tex]

Therefore, the density of the material is [tex]\( 18,360 \, \text{kg/m}^3 \)[/tex].