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प्रश्न
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उत्तर
Three properties of infrared radiations similar to the visible light:
1. They travel in straight lines as light does, with a speed equal to 3 x 108 m/s in vacuum.
2. They obey laws of reflection and refraction.
3. They are unaffected by electric and magnetic fields.
Two properties of infrared radiation different from the visible light:
1. They are absorbed by glass, but they are not absorbed by rock-salt.
2. They are detected by their heating property using a thermopile or a blackened bulb thermometer.
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संबंधित प्रश्न
Describe an activity to show that colours of white light splitted by a glass prism can be recombined to get white light by another identical glass prism. Also draw ray diagram to show the recombination of the spectrum of white light.
In the following diagram the correctly marked angles are :

(a) ∠A and ∠e
(b) ∠i, ∠A and ∠D
(c) ∠A ∠r and ∠e
(b) ∠A ∠r and ∠D
In the figure given alongside, a narrow beam of white light is shown to pass through a triangular glass prism. After passing through the prism, it produces a spectrum YX on the screen.
State the colour seen (i) at X, and (ii) at Y.
A beam of white light falls on a glass prism. The colour of light which undergoes the least bending on passing through the glass prism is:
(a) violet
(b) red
(c) green
(d) blue
The colour of white light which is deviated the maximum on passing through the glass prism is:
(a) blue
(b) indigo
(c) red
(d) orange
An object AB is placed in front of a convex lens as shown in fig. 4. Complete the ray diagram and obtain the image formed and state the nature of the image.

A student has to trace the path of a ray of light through a glass prism. List four precautions he should observe for better results.
Write the range of wavelength of the visible spectrum.
Observe the given figure and write appropriate phenomenon of light in the box.

The sunlight can be split into its constituent colors using ______.
