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Calculate the radius of second Bohr orbit in hydrogen atom from the given data.

Mass of electron = 9.1 x 10^{-31}kg

Charge on the electron = 1.6 x 10^{-19} C

Planck’s constant = 6.63 x 10^{-34} J-s.

Permittivity of free space = 8.85 x 10^{-12} C^{2}/Nm^{2}

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#### Solution

`r_n=((h^2epsilon_0)/(pime^2))n^2`

`:.r_2=((h^2epsilon_0)/(pime^2))(2)^2`

`r_2=((6.63xx10^(-34))^2xx8.85xx10^(-12)xx(2)^2)/(3.14xx9.1xx10^(-31)xx(1.6xx10^(-19))^2)`

`=(43.96 xx 10^-68 xx 8.85 xx 10^-12 xx 4)/(3.14 xx 9.1 xx 10^-31 xx 2.56 xx 10^-38)`

=2.127x10^{-10}m

=2.127 A^{°}

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