JEE Main On 08 April 2018 Question 14

Question: A telephonic communication service is working at carrier frequency of 10 GHz. Only 10% of it is utilized for transmission. How many telephonic channels can be transmitted simultaneously if each channel requires a bandwidth of 5 kHz? [JEE Main Online 08-04-2018]

Options:

A) $ 2\times 10^{5} $

B) $ 2\times 10^{6} $

C) $ 2\times 10^{3} $

D) $ 2\times 10^{4} $

Show Answer

Answer:

Correct Answer: A

Solution:

Carrie Frequency $ \text{=10 }\times\text{ 1}{0^{9}}Hz $

$ \text{10 }\%\text{ is utilised=}\frac{10}{100}\times 10\times 10^{9} $

$ =10^{9}Hz $ Band width $ =5kHz $

No. of channel required $ =\frac{10^{9}}{5\times 10^{3}} $ $ =2\times 10^{5} $