1. Which optical instrument has a large aperture to collect a maximum amount of light from a dim source?
Answer:
Explanation:
Telescopes are designed to observe distant objects, often in low light conditions, thus they have a large aperture to gather as much light as possible.
2. The lens used to correct myopia is:
Answer:
Explanation:
Myopia or nearsightedness is corrected using a concave lens.
3. Which optical instrument uses the phenomenon of total internal reflection?
Answer:
Explanation:
Periscopes use mirrors to achieve total internal reflection and allow viewing over obstructions.
4. In a compound microscope, the lens nearer to the object is called:
Answer:
Explanation:
In a compound microscope, the lens closer to the object is the objective lens.
5. Astigmatism in the human eye is corrected using which type of lens?
Answer:
Explanation:
Astigmatism is caused by an uneven curvature of the cornea and is corrected using cylindrical lenses.
6. The ability of an optical instrument to produce separate images of close objects is known as:
Answer:
Explanation:
Resolving power determines the clarity of the instrument in differentiating between two closely placed objects.
7. The human eye lens is made up of:
Answer:
Explanation:
The lens of the human eye consists of proteins called crystallins.
8. Which optical instrument helps in viewing objects in the dark?
Answer:
Explanation:
Night vision goggles amplify low light levels and help in viewing objects in darkness.
9. The near point of a normal human eye is:
Answer:
Explanation:
For a normal human eye, the nearest point up to which the eye can see clearly without strain is 25 cm.
10. Hypermetropia or farsightedness can be corrected by using which lens?
Answer:
Explanation:
Hypermetropia is corrected using a convex lens.
11. The splitting of white light into its constituent colors is termed as:
Answer:
Explanation:
Dispersion is the phenomenon where white light splits into its constituent colors due to different wavelengths bending by different amounts.
12. The blind spot in the human eye is where:
Answer:
Explanation:
The blind spot is the point where the optic nerve leaves the eye; no vision is possible there as no light-sensitive cells are present.
13. Which lens would you use to spread out a beam of light?
Answer:
Explanation:
A concave lens diverges light, spreading it out.
14. A rainbow is caused by which phenomenon?
Answer:
Explanation:
A rainbow is caused by the combined effects of reflection, refraction, and dispersion of light inside water droplets.
15. The lens which can form a real and virtual image is:
Answer:
Explanation:
A convex lens, depending on the object's position, can form both real and virtual images.