Q30.A 10 kW transmitter emits radio waves of wavelength 500 m. The number of photons emitted per second by the transmitter is of the order of (1) 1037 (2) 1031 (3) 1025 (4) 1043 JEE Main 2012 (12 May Online) JEE Main Previous Year Paper
What This Question Tests
This question requires calculating the energy of a single photon of a given wavelength and then using the power of the transmitter to determine the total number of photons emitted per second.
Concepts Tested
Formulas Used
E = hc/λ
P = N E / t
📚 NCERT Sections This Tests
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?
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.
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12.3 A difference of 2.3 eV separates two energy levels in an atom. What is the frequency of radiation emitted when the atom make a transition from the upper level to the lower level?
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- Photon energy, Power of radiation
- Year
- 2012
- Shift
- 12 May Online
- Q Number
- Q30
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Matter
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