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Question : 11
Total: 12
(a) (i) Arrange the following electromagnetic radiation in the ascending order of their frequencies:mathrm X
(ii) Write two uses of any two of these radiation.
OR(b) With the help of a ray diagram explain the working of a reflecting telescope. Mention two advantages of a reflecting telescope over a refracting telescope.3
(ii) Write two uses of any two of these radiation.
OR(b) With the help of a ray diagram explain the working of a reflecting telescope. Mention two advantages of a reflecting telescope over a refracting telescope.3
Solution:
(a) (i) Arranging in ascending order of frequency:Radio waves, Microwaves, X-rays, Gamma ray(ii) Uses of X-ray:
- to view bones and teeth, for diagnosing fractures.
- to check for cracks or flaws in industrial materials.Uses of infra-red:
- In heat-sensitive thermal imaging cameras.
- In home remote controls.
OR
Parallel light rays from infinite distance initially are incident on two concave objective mirrors. After reflection they are incident on a secondary convex mirror. A virtual image is formed atmathrm F
Advantages of a reflecting telescope over a refracting telescope:
- Mirrors can be made larger in size than lenses.
- There is no chromatic aberrations.
- to view bones and teeth, for diagnosing fractures.
- to check for cracks or flaws in industrial materials.Uses of infra-red:
- In heat-sensitive thermal imaging cameras.
- In home remote controls.
OR
Parallel light rays from infinite distance initially are incident on two concave objective mirrors. After reflection they are incident on a secondary convex mirror. A virtual image is formed at
Advantages of a reflecting telescope over a refracting telescope:
- Mirrors can be made larger in size than lenses.
- There is no chromatic aberrations.
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