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प्रश्न
How does a ray of light bend when it travels from denser to rarer medium.
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उत्तर
When a ray of light travels from denser to rarer medium it bends away from the normal.
संबंधित प्रश्न
Name the factors affecting the critical angle for the pair of media.
Calculate the speed of light in a medium whose critical angle is 30° ?
Swarali has got the following observations while doing an experiment. Answer her questions with the help of observations.
Swarali observed that the light bent away from the normal, while travelling from dense medium to rarer medium. When Swarali increased the values of angle of incidence (i), the values of angle of refraction (r) went on increasing. But at a certain angle of incidence, the light rays returned into the dense medium.
So, Swarali has some questions. Answer them –
a) Name this certain value of ‘i ’. What is the value of ‘r’ at that time ?
b) Name this process of returning of light in dense medium. Explain the process.
(i) Define critical angle.
(ii) State one important factor which affects the critical angle of a given medium.
Name the principle on the basis of which optical fibres work.
Can light be ‘piped’ like sound in a doctor’s stethoscope?
State one factor on which a critical angle for a given pair of media depends. The critical angle for the glass-air interface is 45° for the yellow light. Will it be equal to, less than or greater than 45° for (i) red light, (ii) blue light?
Draw a diagram, properly labelled, to illustrate the use of a total reflecting prism (a right-angled isosceles prism) to turn a ray of light through 180°. Name an instrument in which this device is used.
Solve Numerical example.
A monochromatic ray of light is incident at 37° on an equilateral prism of refractive index 3/2. Determine angle of emergence and angle of deviation. If angle of prism is adjustable, what should its value be for emergent rays to be just possible for the same angle of incidence?
Small air bubbles rising up a fish tank appear silvery when viewed from some particular angle is due to the ______.
