JEE Main20199 Jan 2019Evening ShiftPhysicsCommunication SystemActual
In a communication system operating at wavelength 800 n m , only one percent of source frequency is available as signal bandwidth. The number of channels accommodated for transmitting T V signals of band width 6 M H z are (Take velocity of light c = 3 × 10 8 m / s , h = 6.6 × 10 - 34 J - s )
Options
- A6.25 × 10 5
- B4.87 × 10 5
- C3.75 × 10 6
- D3.86 × 10 6
Correct answer
A. 6.25 × 10 5
Step-by-step solution
Available signal width = 1 100 × c λ = 1 100 × 3 × 10 8 800 × 10 - 9 H z = 3.75 × 10 12 H z Number of available channels = 3.75 × 10 12 6 × 10 6 = 6.25 × 10 5