Q19.An electron moving with speed v and a photon moving with speed c, have the same D-Broglie wavelength. The ratio of the kinetic energy of the electron to that of a photon is: (1) 3c (2) v v 3c (3) v (4) 2c 2c v
What This Question Tests
This problem involves applying Snell's Law at the first surface and the condition for total internal reflection at the second surface to find the maximum incident angle.
Concepts Tested
Formulas Used
n₁sinθ₁ = n₂sinθ₂
sin C = n_r/n_d
📚 NCERT Sections This Tests
11.10 — What Is The De Broglie Wavelength Of
Physics Class 12 · Chapter 11
11.10 What is the de Broglie wavelength of (a) a bullet of mass 0.040 kg travelling at the speed of 1.0 km/s, (b) a ball of mass 0.060 kg moving at a speed of 1.0 m/s, and (c) a dust particle of mass 1.0 × 10–9 kg drifting with a speed of 2.2 m/s ?
11.3 — The Photoelectric Cut-Off Voltage In A Certain Experiment Is 1.5 V.
Physics Class 12 · Chapter 11
11.3 The photoelectric cut-off voltage in a certain experiment is 1.5 V. What is the maximum kinetic energy of photoelectrons emitted?
11.8 — Light Of Frequency 7.21 × 1014 Hz Is Incident On A Metal Surface.
Physics Class 12 · Chapter 11
11.8 Light of frequency 7.21 × 1014 Hz is incident on a metal surface. Electrons with a maximum speed of 6.0 × 105 m/s are ejected from the surface. What is the threshold frequency for photoemission of electrons?
📋 Question Details
- Chapter
- Ray Optics
- Topic
- Total internal reflection
- Year
- 2021
- Shift
- 25 Jul Shift 2
- Q Number
- Q19
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 9: Ray Optics and Optical Instruments
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