The passage describes how Bohr developed his atomic model as an alternative to earlier views, particularly addressing issues with classical physics related to electrons orbiting nuclei and emitting electromagnetic waves.

To summarize:

1. According to Maxwell's theory, accelerated particles like electrons should emit energy in the form of electromagnetic waves.

2. This raised a problem for classical models because if an electron continuously emitted energy while spiraling towards its nucleus, it would eventually collapse into the center due to conservation laws.

3. To resolve this paradoxical outcome within classical physics, Bohr proposed that electrons could only orbit at specific (discrete) distances from the nucleus rather than being able to be found anywhere in between these orbits.

Bohr's model also introduced several key concepts:

1. The idea of quantized energy levels: Each electron orbital had a unique amount of potential energy associated with it, and transitions between these energy states could only occur through specific (quantized) amounts of energy being absorbed or released.

2. Quantization of angular momentum: Bohr further proposed that the total angular momentum of an orbiting electron must always be quantized in integral multiples of h/2π.

These ideas were revolutionary at the time because they departed from classical physics' continuous view and introduced a more granular, discrete understanding of physical phenomena.

Bohr atomic models