Question

A coin has a mass of 7.0g. It is made of a metal alloy of density 5.6g/cm3. Calculate the volume of the coin.

Answer 1

`\text{Density,}\\\\~~~~~~~~\rho = \frac mV\\\\\\\implies V = \frac m{\rho}\\\\\\\implies V = \frac{7 * 10^(-3)~ \text{kg}}{\tfrac{5.6 * 10^(-3)~ \text{kg}}{ 10^(-6) ~\text{m}^3} }\\\\ \\\implies V = \frac{7 * 10^(-3)~ \text{kg}}{5.6 * 10^(-3) * 10^6~~ \text{kg}~ \text{m}^(-3)}\\\\\\ \implies V = 1.25 * 10^(-6)~ \text m^3\\\\\\\implies V =0.00000125~ \text m^3\\\\\text{Hence the volume of the coin is 0.00000125}~ \text m^3`

Answer 2

Volume = mass/density

Converting grams to kilograms
7.0 = 0.007
5.6 = 0.0056

Volume = 0.007/0.0056
Volume = 1.25 m^3