English
Karnataka Board PUCPUC Science 2nd PUC Class 12

Show that the first few frequencies of light that is emitted when electrons fall to the nth level from levels higher than n, are approximate harmonics (i.e. in the ratio 1 : 2 : 3...) when n >> 1.

Advertisements
Advertisements

Question

Show that the first few frequencies of light that is emitted when electrons fall to the nth level from levels higher than n, are approximate harmonics (i.e. in the ratio 1 : 2 : 3...) when n >> 1.

Short/Brief Note
Advertisements

Solution

`v_(mn) = cRZ^2 [1/(n + p)^2 - 1/n^2]`, where m = n + p, (p = 1, 2, 3, ...) and R is Rydberg constant.

For p << n.

`v_(mn) = cRZ^2 [1/n^2 (1 + p/n)^-2 - 1/n^2]`

`v_(mn) = cRZ^2 [1/n^2 - (2p)/n^3 - 1/n^2]`

`v_(mn) = cRZ^2 (2p)/n^3 ≃ ((2cRZ^2)/n^3)p`

Thus, νmn are approximately in the order 1, 2, 3...........

shaalaa.com
  Is there an error in this question or solution?
Chapter 12: Atoms - Exercises [Page 79]

APPEARS IN

NCERT Exemplar Physics Exemplar [English] Class 12
Chapter 12 Atoms
Exercises | Q 12.22 | Page 79

RELATED QUESTIONS

What is the shortest wavelength present in the Paschen series of spectral lines?


In both β and β+ decay processes, the mass number of a nucleus remains the same, whereas the atomic number Z increases by one in β decay and decreases by one in β+ decay. Explain giving reason.


Which of the following is TRUE?


If wavelength for a wave is `lambda = 6000  Å,` then wave number will be ____________.


Which of the following transition will have highest emission frequency?


The energy (in eV) required to excite an electron from n = 2 to n = 4 state in hydrogen atom is ____________.


If the mass of the electron is reduced to half, the Rydberg constant ______.


In hydrogen spectrum, the wavelengths of light emitted in a series of spectral lines is given by the equation, `1/lambda` = R `(1/4^2 - 1/"n"^2)`, where n = 5, 6, 7...... and 'R' is Rydberg's constant. Identify the series and wavelength region.


Continuous spectrum is produced by ______.


To produce an emission spectrum of hydrogen it needs to be ______.


Determine the series limit of Balmer, Paschen and Brackett series, given the limit for Lyman series is 911.6 Å.


The first three spectral lines of H-atom in the Balmer series are given λ1, λ2, λ3 considering the Bohr atomic model, the wavelengths of the first and third spectral lines `(lambda_1/lambda_3)` are related by a factor of approximately 'x' × 10–1. The value of x, to the nearest integer, is ______.


In the hydrogen atoms, the transition from the state n = 6 to n = 1 results in ultraviolet radiation. Infrared radiation will be obtained in the transition.


The frequency of the series limit of the Balmer series of the hydrogen atoms of Rydberg’s constant R and velocity of light c is ______.


Calculate the wavelength of the first two lines in the Balmer series of hydrogen atoms.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×