Recall Bohr’s atomic model theory. The Bohr Model of the Atom In 1911 at the age of 25, Niels Bohr received his Ph.D. in physics. He was convinced that the atom could be pictured as a small positive nucleus with electrons orbiting around it
The electrons revolve rapidly around the nucleus in fixed circular paths called energy levels or shells. when an electron jumps from a lower energy level to a higher one, some energy is absorbed while some energy is emitted. The energy change is given by delta E=hc / wavelength.
The Bohr model of the atom, at first, appeared to be a good theory, and, indeed, it was an advance over what had gone before. But as scientists learned more about the atom its flaws became evident, and it was seen to be incorrect, eventually to be superseded by quantum theory.