ANSWER: D
ANSWER: B
ANSWER: A
The formation of glittering colour in thin foam of soap is the result of the phenomenon of total reflection and interference.
When light waves hit a bubble, some of them bounce straight back off the outer part of the soap film.
Others refracted on through but then bounce off the inner part of the film.
Now refracted and reflected light gives soap foam glittering colour.
When two light waves from different coherent sources meet together, then the distribution of energy due to one wave is disturbed by the other. This modification in the distribution of light energy due to super- position of two light waves is called “Interference of light”.
Answer: (D)
Answer: A
Ans. (a) The optical fibre is a very thin strand of glass (silica) or plastic cable for transmitting light from one point to another. It works on the principle of total internal reflection. There is no loss of signal through an optical fibre.
ANSWER: C
A diamond sparkles more than a glass crystal of the same shape and size, because the refractive index of diamond is very high (u = 2.42). Therefore its critical angle get reduced which results in less opportunity for light to exit. So the light reflects off the diamond’s inner surfaces several times before it finally exits. The refractive index of glass is 1.51. Thus, statement A is true but reason R is false.
ANSWER: A
When a ray of light travels from a denser medium to a rarer medium it speeds up and bends away from the normal. If ray of light travels from a rarer to a denser medium, it slows down and bends towards the normal in the denser medium
Answer: B
Answer: C
Answer: C
© 2025 Civilstap Himachal Design & Development