Bohr Atom Model: Electron Shells & Photon Emission (2D)

This 2D companion drives the same hydrogen-like Bohr model as the 3D version through a plain canvas view built for reading the physics rather than orbiting a scene: an atomic-number slider re-fills real electron shells (capacity 2n², capped at 32) around a proton/neutron nucleus, each shell's orbital radius, orbital speed and energy level are computed from the standard Bohr formulas (r_n = n²a₀/Z, v_n = Zv₀/n, E_n = −13.6Z²/n² eV) and shown live, and clicking any electron excites it one or two shells outward — when it spontaneously falls back roughly a second later, the panel reports the transition's photon energy and wavelength, and a ring flash tinted to that wavelength expands from the electron, making Bohr's explanation of atomic emission spectra directly interactive instead of implied.