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The radius of atom is of the order of 1 Å and the radius of nucleus is of the order of fermi. How many magnitudes higher is the volume of atom as compared to the volume of nucleus?
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Solution
Radius of atom = 1 Å = 10^{–10} m
Radius of nucleus = 1 fermi = 10^{–}^{15} m
Volume of atom = V_{A} = `4/3 πR_A^3`
Volume of atom = `4/3 πR_A^3`
Volume of nucleus V_{N} = `4/3 πR_N^3`
`V_A/V_N = (4/3 πR_A^3)/(4/3 πR_N^3)`
= `(R_A/R_N)^3`
= `(10^-10/10^-15)^3`
= 10^{15}
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