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Question
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 = VA = `4/3 πR_A^3`
Volume of atom = `4/3 πR_A^3`
Volume of nucleus VN = `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`
= 1015
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