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Question
Evaluate Rydberg constant by putting the values of the fundamental constants in its expression.
Solution
Expression of Rydberg constant (R) is given by
`R = (me^4)/(8h^2c ∈_0^2)`
Mass of electron, me = `9.31 xx 10^21 xx kg `
Charge, e = 1.6 × 10−19 C
]Planck's constant, h = 6.63 × 10−34 J-s,
Speed of light, c = 3 × 108 m/s,
Permittivity of vacuum, ∈0 = 8.85 × 10−12 C2N1m
On substituting the values in the expression, we get
`R = ((9.31xx10^-31)xx(1.6xx10^-19)^4)/(8 xx(6.63xx10^-14)^2 xx (3xx10^8)xx(8.85xx10^-12)^2`
`rArr R = 1.097 xx 10^7 m^-1`
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