Why the total energy of atomic electron is negative ?

Explanation

To understand why the total energy of an atomic electron is negative, we can break down the explanation into several steps:

### Step 1: Define Total Energy
The total energy of an electron in an atom is the sum of its kinetic energy (due to its motion) and potential energy (due to its position in the electric field created by the nucleus).

### Step 2: Energy at Infinite Distance
At an infinite distance from the atom, the electron is considered to be free and not influenced by the nucleus. In this state, the total energy of the electron is defined as zero. This serves as our reference point.

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