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प्रश्न
Find the maximum Coulomb force that can act on the electron due to the nucleus in a hydrogen atom.
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उत्तर
Charge on the electron, q1 = `1.6 xx 10^-19 C`
Charge on the nucleus, q2 = `1.6 xx 10^-19 C`
Let r be the distance between the nucleus and the electron.
Coulomb force (F) is given by
`F = (q_1q_2)/(4 pi∈_0r^2) ........(1)`
Here , q1 = q2 = q = 1.6`xx 10^-19C`
000 Smallest distance between the nucleus and the first orbit, r = 0.53 `r = 0.53xx10^-10m `
`K= 1/(4piepsilon_0) = 9 xx 10^9Nm^2C^-2`
Substituting the respective values in (1), we get
`F =((9xx10^9)xx(1.6xx10^-19)xx(1.6xx10^-19))/(0.53xx10^-10)^2`
= `(1.6xx1.6xx9xx10^-9)/(0.53) = 82.02 xx 10^-9`
= `8.2xx10^-8 N`
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संबंधित प्रश्न
Classically, an electron can be in any orbit around the nucleus of an atom. Then what determines the typical atomic size? Why is an atom not, say, a thousand times bigger than its typical size? The question had greatly puzzled Bohr before he arrived at his famous model of the atom that you have learnt in the text. To simulate what he might well have done before his discovery, let us play as follows with the basic constants of nature and see if we can get a quantity with the dimensions of length that is roughly equal to the known size of an atom (~ 10−10 m).
(a) Construct a quantity with the dimensions of length from the fundamental constants e, me, and c. Determine its numerical value.
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- if we measure the frequencies of light emitted due to transitions between excited states and the first excited state.
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