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Question
| A compound microscope consists of two converging lenses. One of them, of smaller aperture and smaller focal length, is called objective and the other of slightly larger aperture and slightly larger focal length is called eye-piece. Both lenses are fitted in a tube with an arrangement to vary the distance between them. A tiny object is placed in front of the objective at a distance slightly greater than its focal length. The objective produces the image of the object which acts as an object for the eye-piece. The eye-piece, in turn, produces the final magnified image. |
The magnification due to a compound microscope does not depend upon ______.
Options
the aperture of the objective and the eye-piece
the focal length of the objective and the eye-piece
the length of the tube
the colour of the light used
Solution
The magnification due to a compound microscope does not depend upon the aperture of the objective and the eye-piece.
Explanation:
Magnification when the image is formed at the near point of distinct vision is `"L"/"f"_"o"(1 + "D"/"f"_"e")`.
Magnification, when the image is formed at, is `"L"/"f"_"o" "D"/"f"_"e"`.
No expression contains the aperture terms. So, magnification does not depend on the aperture of the objective and the eye-piece.
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| A compound microscope consists of two converging lenses. One of them, of smaller aperture and smaller focal length, is called objective and the other of slightly larger aperture and slightly larger focal length is called eye-piece. Both lenses are fitted in a tube with an arrangement to vary the distance between them. A tiny object is placed in front of the objective at a distance slightly greater than its focal length. The objective produces the image of the object which acts as an object for the eye-piece. The eye-piece, in turn, produces the final magnified image. |
Which of the following is not correct in the context of a compound microscope?
