NTA Abhyas JEE Main2020PhysicsAtomic PhysicsPractice
A hydrogen atom initially in the ground level absorbs a photon which excites it to the n = 4 level. Determine the wavelength of the photon.
Options
- A8.6 × 10 − 7 m
- B9.8 × 10 − 8 m
- C7.4 × 10 − 8 m
- D8.2 × 10 − 8 m
Correct answer
B. 9.8 × 10 − 8 m
Step-by-step solution
1 λ = R ( 1 n 1 2 − 1 n 2 2 ) 1 λ = 1.09 × 10 7 ( 1 1 2 − 1 4 2 ) = 1.09 × 10 7 ( 16 − 1 16 ) = 1.09 × 10 7 × 15 16 λ = 16 1.09 × 15 × 10 7 = 9.8 × 10 − 8 m