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Hydrogen atom initially in… (Class 12 Physics 2023, Q11)

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PhysicsCBSE Class 12 · Board exam 2023, set 55/1/1 · 1 mark · MCQ

CBSE Class 12 Physics 2023: question 11

Set in the CBSE Class 12 board exam of 2023, paper 55/1/1, section A, question 11, for 1 mark. Try it first; the hints and our step-by-step solution are below.

Q11 · 1 mark · MCQAtoms

Hydrogen atom initially in the ground state, absorbs a photon which excites it to n = 5 level. The wavelength of the photon is :

  1. (A)975 nm
  2. (B)740 nm
  3. (C)523 nm
  4. (D)95 nm

Source: official question paper from cbse.gov.in (PDF). See it in the full 2023 board paper, set 55/1/1.

Hints

Open one hint at a time and try again before the next.

Hint 1

Find using eV.

Hint 2

Use with eV nm.

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. The energy absorbed is eV.

    ½ mark

  2. nm. This is option (D).

    ½ mark

Answer: 95 nm, option (D)

Where the marks are

  • Finds the energy difference and converts it to wavelength, 95 nm (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Atoms, one at a time, marked against the answer key and marking points.Back to the full paper2023 board paper, set 55/1/1: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.