The total energy of eletcron in the ground state of hydrogen atom is `-13.6 eV`. The kinetic enegry of an electron in the first excited state is

Explanation

To find the kinetic energy of an electron in the first excited state of a hydrogen atom, we can follow these steps:

### Step 1: Understand the Energy Formula
The total energy \( E_n \) of an electron in the nth orbit of a hydrogen atom is given by the formula:
\[ E_n = -\frac{13.6 \, \text{eV}}{n^2} \]
where \( n \) is the principal quantum number (orbit number).
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