## Question

### Solution

Correct option is

+3.4 eV

The kinetic and potential energies of an electron in the nth excited state are given by  adding (i) and (ii) we get the total energy E which is  Notice from (i) and (iii) that E = –KE. Given E = –3.4 eV.

Hence    KE = –E = –(–3.4) = +3.4 eV.

#### SIMILAR QUESTIONS

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Q9

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