The angular momentum for the electron in Bohr's orbit is L. If the electron is assumed to revolve in second orbit of hydrogen atom, then the change in angular momentum will be

Solution

Physics sir · 3 steps

Bohr angular momentum rises in equal steps of h/2π, so orbit 1 to orbit 2 adds exactly L.

1. Bohr's quantisation. In Bohr's model the angular momentum in the nth orbit can only be a whole-number multiple of h/2π.

   Lₙ = nh/2π

2. First and second orbit. The given L is the value in the first orbit, so L = h/2π. In the second orbit, L₂ = 2h/2π = 2L.
3. So. The change is L₂ - L₁ = 2L - L = L, which is option (a).

The idea to keep. Bohr angular momentum is nh/2π, so it grows in equal steps. Moving up by one orbit always changes it by exactly h/2π, whichever orbit you start from.

Answer from the NTA final answer key. Solution by PrepWiser.