Q17.A metallic surface is illuminated with radiation of wavelength ๐, the stopping potential is ๐0. If the same ๐0 surface is illuminated with radiation of wavelength 2๐, the stopping potential becomes . The threshold 4 wavelength for this metallic surface will be (1) 3๐ (2) 4๐ (3) 3 (4) ๐ 2๐ 4
What This Question Tests
This question is a direct application of the concept of critical angle and its relation to the refractive indices and speeds of light in two media.
Concepts Tested
Formulas Used
sin(C) = n_rarer / n_denser
n = c/v
๐ NCERT Sections This Tests
11.8 โ Light Of Frequency 7.21 ร 1014 Hz Is Incident On A Metal Surface.
Physics Class 12 ยท Chapter 11
11.8 Light of frequency 7.21 ร 1014 Hz is incident on a metal surface. Electrons with a maximum speed of 6.0 ร 105 m/s are ejected from the surface. What is the threshold frequency for photoemission of electrons?
11.6 โ The Threshold Frequency For A Certain Metal Is 3.3 ร 1014 Hz. If Light
Physics Class 12 ยท Chapter 11
11.6 The threshold frequency for a certain metal is 3.3 ร 1014 Hz. If light of frequency 8.2 ร 1014 Hz is incident on the metal, predict the cut- off voltage for the photoelectric emission.
11.9 โ Light Of Wavelength 488 Nm Is Produced By An Argon Laser Which Is
Physics Class 12 ยท Chapter 11
11.9 Light of wavelength 488 nm is produced by an argon laser which is used in the photoelectric effect. When light from this spectral line is incident on the emitter, the stopping (cut-off) potential of photoelectrons is 0.38 V. Find the work function of the material from which the emitter is made.
๐ Question Details
- Chapter
- Ray Optics
- Topic
- Total Internal Reflection
- Year
- 2023
- Shift
- 11 Apr Shift 1
- Q Number
- Q17
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 9: Ray Optics and Optical Instruments
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