Physics Practice: Refraction through Lenses (Mock Test 5 - Ultimate Comprehensive)
1. A beam of light parallel to the principal axis of a concave lens, after refraction, appears to diverge from:
2. If a convex lens is used as a magnifying glass, the image formed is:
3. Two thin lenses of power $+3.5 \text{ D}$ and $-1.5 \text{ D}$ are placed in contact. The focal length of the combination is:
4. Linear magnification is positive when the image is ________ and negative when it is ________.
5. An object is placed $25 \text{ cm}$ from a convex lens of focal length $25 \text{ cm}$. The image is formed at:
6. A concave lens of focal length $20 \text{ cm}$ forms an image at $10 \text{ cm}$ from the lens. The object distance is:
7. The power of a lens is $-4.0 \text{ D}$. Its nature and focal length are:
8. A ray of light incident at the optical center of a lens ________.
9. Which of the following is used in a terrestrial telescope to make the final image erect?
10. To produce a magnification of $-1$ with a convex lens of focal length $f$, the object distance should be:
11. A virtual image is formed by a convex lens when the object is placed between:
12. The magnification of a concave lens is always ________.
13. Which rule is followed for the sign of focal length $f$?
14. If an object moves towards a convex lens from infinity to $F$, its real image moves from:
15. The linear magnification $m$ in terms of $u$ and $f$ for a lens is:
16. For a lens, the distance of the image ($v$) is positive when the image is ________.
17. A convex lens forms a real, inverted image of a house on a screen. If the house is very far, the screen is at:
18. The power of a lens ________ when its focal length is increased.
19. If the magnification is $+0.5$, the lens must be ________.
20. The principal axis is a line passing through ________ and ________ of the lens.
