| 1 |
Sun light consist of ____________ colour |
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| 2 |
A normal eye can see near objects clearly at a distance of: |
- A. 20 cm
- B. 25 cm
- C. 30 cm
- D. 35 cm
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| 3 |
Speed of light in air is ms<sup>-1</sup> |
- A. 3 x 10<sup>8</sup>
- B. 3 x 10<sup>11</sup>
- C. 3 x 10<sup>5</sup>
- D. 340
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| 4 |
The refractive index of air is: |
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| 5 |
Optical fibers work on the principle of: |
- A. Refraction
- B. Reflection
- C. Total internal reflection
- D. Diffraction
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| 6 |
Power of convex lens is 10 D. Its focal length is: |
- A. 100 m
- B. 10 m
- C. 1 m
- D. 0.1 m
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| 7 |
Focal length for concave mirror is : |
- A. -ve
- B. +ve
- C. same
- D. none of these
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| 8 |
The mirror whose inner surface is reflecting is called: |
- A. Concave mirror
- B. Convex mirror
- C. Miroor
- D. Lens
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| 9 |
The critical angle for glass to: |
- A. 24<sup>o</sup>
- B. 48<sup>o</sup>
- C. 42<sup>o</sup>
- D. 50<sup>o</sup>
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| 10 |
After refraction from a convex lens, rays of light parallel to the principal axis converge at a point, this point of convex lens is called: |
- A. Principal focus
- B. Pole
- C. Focal length
- D. Optical center
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