Calculate the velocity of an electron revolving in the second orbit of a hydrogen atom from the given data

Explanation

To calculate the velocity of an electron revolving in the second orbit of a hydrogen atom, we can follow these steps:

### Step 1: Understand the formula for kinetic energy
The kinetic energy (KE) of an electron in an orbit can be expressed as:
\[ KE = -\frac{13.6 \, \text{eV} \cdot Z^2}{n^2} \]
where:
...