Q17.A parallel beam of light of wavelength 900 nm and intensity 100 Wm−2 is incident on a surface perpendicular to the beam. The number of photons crossing 1 cm2 area perpendicular to the beam in one second is (1) 3 × 1016 (2) 4. 5 × 1016 (3) 4. 5 × 1017 (4) 4. 5 × 1020
What This Question Tests
This question tests the effect of placing the YDSE setup in a medium of different refractive index on the fringe width, requiring knowledge of how wavelength changes.
Concepts Tested
Formulas Used
β = (λD)/d
λ_medium = λ_air / μ
📚 NCERT Sections This Tests
10.5 — In Young’S Double-Slit Experiment Using Monochromatic Light Of
Physics Class 12 · Chapter 10
10.5 In Young’s double-slit experiment using monochromatic light of wavelength l, the intensity of light at a point on the screen where path difference is l, is K units. What is the intensity of light at a point where path difference is l/3?
10.4 — In A Young’S Double-Slit Experiment, The Slits Are Separated By
Physics Class 12 · Chapter 10
10.4 In a Young’s double-slit experiment, the slits are separated by 0.28 mm and the screen is placed 1.4 m away. The distance between the central bright fringe and the fourth bright fringe is measured to be 1.2 cm. Determine the wavelength of light used in the experiment.
11.4 — Monochromatic Light Of Wavelength 632.8 Nm Is Produced By A
Physics Class 12 · Chapter 11
11.4 Monochromatic light of wavelength 632.8 nm is produced by a helium-neon laser. The power emitted is 9.42 mW. (a) Find the energy and momentum of each photon in the light beam, (b) How many photons per second, on the average, arrive at a target irradiated by this beam? (Assume the beam to have uniform cross-section which is less than the target area), and (c) How fast does a hydrogen atom have to travel in order to have the same momentum as that of the photon?
📋 Question Details
- Chapter
- Wave Optics
- Topic
- Young's Double Slit Experiment (YDSE)
- Year
- 2022
- Shift
- 26 Jul Shift 1
- Q Number
- Q17
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 10: Wave Optics
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