Q61.Given below are two statements about X-ray spectra of elements : Statement (I) : A plot of √v ( v = frequency of X -rays emitted) vs atomic mass is a straight line. Statement (II) : A plot of v(v = frequency of X -rays emitted) vs atomic number is a straight line. In the light of the above statements, choose the correct answer from the options given below : (1) Both Statement I and Statement II are true (2) Statement I is false but Statement II is true (3) Both Statement I and Statement II are false (4) Statement I is true but Statement II is false
What This Question Tests
This question tests the understanding of Moseley's Law, which describes the relationship between the frequency of characteristic X-rays and the atomic number of the element. It differentiates between atomic mass and atomic number's influence on X-ray spectra.
Concepts Tested
Formulas Used
√v = a(Z - b)
📚 NCERT Sections This Tests
12.1 — Choose The Correct Alternative From The Clues Given At The End Of
Physics Class 12 · Chapter 12
12.1 Choose the correct alternative from the clues given at the end of the each statement: (a) The size of the atom in Thomson’s model is .......... the atomic size in Rutherford’s model. (much greater than/no different from/much less than.) (b) In the ground state of .......... electrons are in stable equilibrium, while in .......... electrons always experience a net force. (Thomson’s model/ Rutherford’s model.) (c) A classical atom based on .......... is doomed to collapse. (Thomson’s model/ Rutherford’s model.) (d) An atom has a nearly continuous mass distribution in a .......... but has a highly non-uniform mass distribution in .......... (Thomson’s model/ Rutherford’s model.) (e) The positively charged part of the atom possesses most of the mass in .......... (Rutherford’s model/both the models.)
12.1 — (A) No Different From
Physics Class 12 · Chapter 12
12.1 (a) No different from (b) Thomson’s model; Rutherford’s model (c) Rutherford’s model (d) Thomson’s model; Rutherford’s model (e) Both the models
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
📋 Question Details
- Chapter
- Atoms
- Topic
- Moseley's Law and X-ray Spectra
- Year
- 2025
- Shift
- 23 Jan Shift 2
- Q Number
- Q61
- Type
- Assertion Reasoning
- NCERT Ref
- Class 12 Physics Ch 12: Atoms
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