Q29.In a communication system operating at wavelength 800 nm, only one percent of source frequency is available as signal bandwidth. The number of channels accommodated for transmitting TV signals of band width 6 MHz are (Take velocity of light c = 3 × 108 m/s, h = 6.6 × 10−34 J-s ) (1) 6.25 × 105 (2) 4.87 × 105 (3) 3.75 × 106 (4) 3.86 × 106
What This Question Tests
This question requires calculating the carrier frequency from the wavelength, then determining the available signal bandwidth as a percentage of the carrier frequency, and finally finding the number of channels that can be accommodated.
Concepts Tested
Formulas Used
c = fλ
Available bandwidth = percentage * source frequency
Number of channels = Available bandwidth / Channel bandwidth
📚 NCERT Sections This Tests
11.6 — The Threshold Frequency For A Certain Metal Is 3.3 × 1014 Hz. If Light
Physics Class 12 · Chapter 11
11.6 The threshold frequency for a certain metal is 3.3 × 1014 Hz. If light of frequency 8.2 × 1014 Hz is incident on the metal, predict the cut- off voltage for the photoelectric emission.
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.
12.3 — A Difference Of 2.3 Ev Separates Two Energy Levels In An Atom. What
Physics Class 12 · Chapter 12
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
- Communication Systems
- Topic
- Bandwidth in communication
- Year
- 2019
- Shift
- 09 Jan Shift 2
- Q Number
- Q29
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 15: Communication Systems
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