NTA Abhyas JEE Main2020PhysicsAtomic PhysicsPractice
When an electron jumps from a level n = 4 to n = 1 , momentum of the recoiled hydrogen atom will be
Options
- A6.8 × 10 - 27 k g m s - 1
- B12.75 × 10 - 19 k g m s - 1
- C13.6 × 10 - 19 k g m s - 1
- Dzero
Correct answer
A. 6.8 × 10 - 27 k g m s - 1
Step-by-step solution
E = E 4 - E 1 = - 13.6 4 2 — - 13.6 1 2 = - 0.85 + 13.6 = 12.75 e V = 12.75 × 1.6 × 10 - 19 J P = E c = 12.75 × 1.6 × 10 - 19 3 × 10 8 = 6.8 × 10 - 27 k g m s - 1 This must be the momentum of recoiled hydrogen atom (in opposite direction)