Which of the following phenomena is used in optical fibres ? (a) Total internal reflection

Answer: Regular reflection  Diffused reflection 1 When all the parallel rays reflected from a plane surface are parallel, the reflection is known as regular reflection When all the parallel rays reflected from a plane surface...

(a) Total internal reflection is used in optical fibres.

(b) : Optical fibres are subject to electromagnetic intereference from outside.

(b) light goes from optically denser medium to rarer medium EXPLANATION:  When the light goes from a denser medium to lighter medium, it goes away from the normal. When the angle of...

(b) According to Snell’s Law,  sin i/ sin r =μ 2/μ 1 = where r = 90º for particular incidence angle called critical angle. When the incidence angle is equal to or greater than...

(c) For total internal reflection light ray must travel from optically denser to an optically rarer medium.

(b) Difference between apparent and real depth of a pond is due to the refraction of light, not due to the total internal reflection. Other three phenomena are due to...

(a) The apparent flattening (oval shape) of the sun at sunset and sunrise is due to refraction

(a) An optical fibre is a thin, flexible, transparent fibre that acts as a waveguide or "light pipe" to transmit light between the two ends of the fibre. An optical...

(c) Convection currents of hot air rising off a surface have a lower density than the air directly above it. The difference in density cause light passing through the air...