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प्रश्न
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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उत्तर
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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संबंधित प्रश्न
The principle of ‘parallax’ in section 2.3.1 is used in the determination of distances of very distant stars. The baseline AB is the line joining the Earth’s two locations six months apart in its orbit around the Sun. That is, the baseline is about the diameter of the Earth’s orbit ≈ 3 × 1011m. However, even the nearest stars are so distant that with such a long baseline, they show parallax only of the order of 1” (second) of arc or so. A parsec is a convenient unit of length on the astronomical scale. It is the distance of an object that will show a parallax of 1” (second) of arc from opposite ends of a baseline equal to the distance from the Earth to the Sun. How much is a parsec in terms of meters?
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