Why is the negative sign for energy of the electron in hydrogen atom for all possible orbits?

Explanation

Energy of the electron in the atom is lower than that of a free electron at rest (at infinite distance from the nucleus and having energy equal to zero), `E_(alpha)= 0`. As the electron gets closer to the nucleus, the absolute value of energy `(E_(n))` becomes larger and more and more negative. The most negative value corresponds to n= which is the most stable orbit..