Question

a thin sheet of of gold foil has an area of 3.05 cm^2 and a mass of 6.3 mg. how thick is the foil? the mass density of gold is 19,300 kg/(m^3)​

Answer 1

Given:-

Area of foil, A=$3.05cm^{2}=3.05\times10^{-4}m^{2}$

mass of foil, m=6.3 mg=$6.3\times10^{-3}kg$

mass density of gold, $\rho=19300kg/m^{3}$

To Find:-

thickness of foil

Explanation:-

$\text{Let 't' be the thickness of the foil}\\\\\text{We know that, density is given by}(\rho)=\dfrac{mass(m)}{Volume(V)}\\\\\Rightarrow \rho=\dfrac{m}{A\times t}\\\\\Rightarrow19300=\dfrac{6.3\times10^{-3}}{3.05\times10^{-4}\times t}\\\\\Rightarrow t=1.07\times10^{-3}m=1.07mm$