In Bohr's atom, the energy levels are En=−n2E0 where E0 is the ground state energy.
Given E=−0.04E0, we have −n2E0=−0.04E0, which gives n2=25, so n=5.
The angular momentum in Bohr's model is L=nℏ=n2πh.
Therefore, h2πL=h2π×n2πh=n=5.
JEE Main 2026 — Physics Modern Physics
The energy of an electron in an orbit of the Bohr's atom is −0.04E0eV where E0 is the ground state energy. If L is the angular momentum of the electron in this orbit and h is the Planck's constant, then h2πL is ____ :
Held on 21 Jan 2026 · Verified 6 Jul 2026.
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