Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app

NTA Abhyas 2020

Exam: NTA Abhyas
Year: 2020
Subject: Physics
Chapter: Communication System

NTA Abhyas 2020 · Physics · Communication System

The glass of optical fibre has a refractive index 1. 55 and...

The glass of optical fibre has a refractive index

1. 55

and cladding with another glass of refractive index

1. 51

. When the surrounding medium is air, the numerical aperture will be

Options

A $0. 625$
B $0. 350$
C $0. 528$
D $0. 704$

Correct answer

B. $0. 350$

Step-by-step solution

For air,

{\mu}_{0} = 1

. Here,

{\mu}_{1} = 1.55, {\mu}_{2} = 1.51

NA = \dfrac{\sqrt{{\mu}_{1}^{2} - {\mu}_{2}^{2}}}{{\mu}_{0}}

= \dfrac{\sqrt{{\left(1.55\right)}^{2} - {\left(1.51\right)}^{2}}}{1} = 0.350

Practice Communication System on Quantrex Academy →

More from Communication System

The height of transmitting antenna is 180m and the height of the receiving antenna is… JEE Main 2023 To radiate EM signal of wavelength λ with high efficiency, the antennas should have a… JEE Main 2023 Match List-I with List-II List-I (Layer of atmosphere) List-II (Approximate height over… JEE Main 2023 The amplitude of 15 ( 1000 ) is modulated by 10 ( 4 ) signal. The amplitude modulated… JEE Main 2023 In satellite communication, the uplink frequency band used is: JEE Main 2023 A transmitting antenna is kept on the surface of the earth. The minimum height of… JEE Main 2023 A massage signal of frequency 3kHz is used to modulate a carrier signal of frequency 1 .… JEE Main 2023 A carrier wave of amplitude 15V is modulated by a sinusoidal base band signal of… JEE Main 2023 Full Communication System list All NTA Abhyas JEE Main PYQs