QJEEM18Phb7cb: JEE Main 2018 Physics - Class 12 JEEM18Phb7cb Solution: Both the nucleus and the atom of some element arein their…

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QJEEM18Phb7cb: JEE Main 2018 Physics - Class 12 JEEM18Phb7cb Solution: Both the nucleus and the atom of some element arein their…

Both the nucleus and the atom of some element arein their respective first excited states. They get de-excted by emitting photons of wavelengths ^$λ$N, ^$λ$A respectively. The ratio

\frac{^{λ} N}{^{λ} A}

is closest to :

Multiple Choice Options

A 10−6
B 10
C 10−10
D 10−1

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Accepted Answer

We know that $E = \frac{h c}{λ}$

So, for atom $E_{A} = \frac{h c}{λ_{A}}$

And for neutron $E_{N} = \frac{h c}{λ_{N}}$

Then, $\frac{E_{A}}{E_{N}} = \frac{h c}{λ_{A}} \times \frac{λ_{N}}{h c} \Rightarrow \frac{λ_{N}}{λ_{A}}$

Here, E_A is order of eV and E_N is order of MeV.

Therefore, $\frac{λ_{N}}{λ_{A}} = \frac{E_{A}}{E_{N}} = \frac{e V}{M e V} = \frac{1 e V}{10^{6} e V}$

$λ_{N} = 10^{- 6} λ_{A}$

QJEEM18Phb7cb: JEE Main 2018 Physics - Class 12 JEEM18Phb7cb Solution: Both the nucleus and the atom of some element arein their…

Multiple Choice Options

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