Number of spectral lines emitted when a hydrogen atom de-excites from n = 4 to n = 1 (all possible cascades) is:
A3
B4
C6
D10
Answer & Solution
Correct answer: C. 6
n(n−1)/2 = 4·3/2 = 6 lines.
Related questions
The de-Broglie wavelength associated with a particle of mass $10^{-6}$ kg with a velocity The following diagram indicates the energy levels of a certain atom when the system moves A radioactive sample consists of two distinct species having equal number of atoms initialThe figure shows the variation of photocurrent with anode potential for a photo-sensitive A waveform shown when applied to the following circuit will produce which of the followingThe difference between the incident energy and threshold energy for an electron in a photoThe dimensions of Planck's constant are same as that of:For the ground state of singly ionised helium (He⁺, Z = 2), the energy of the electron is: