In case of compound microscope which of the following statements is/are correct? 1) The focal length of eye piece is larger than the focal length of the objective 2) The focal length of the eye piece is smaller than the focal length of the objective 3) The image produced in a normal optical microscope is real 4) The image produced in a normal optical microscope is virtual
In case of compound microscope which of the following statements is/are correct? 1) The focal length of eye piece is larger than the focal length of the objective 2) The focal length of the eye piece is smaller than the focal length of the objective 3) The image produced in a normal optical microscope is real 4) The image produced in a normal optical microscope is virtual Correct Answer 1 and 4
CONCEPT:
Compound microscope:
- A compound microscope is an optical instrument that is used to obtain highly magnified images.
- It uses a set of two lenses
- Eyepiece lens
- Objective lens.
- Generally, the eyepiece used is of lower power than that of the objective lens.
- A typical working of the compound microscope is as shown
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- Magnification of a compound microscope (m) is given by the formula
⇒ m = mo × me
Where mo is the magnifying power of the objective lens and me is the magnifying power of the eyepiece.
EXPLANATION:
- The focal length of the eyepiece lens is larger than the focal length of the objective lens. So statement 1 is correct.
- When an object is placed between the focus and the lens then the image formed by the convex lens is virtual and enlarged.
- As the lens used in the microscope is a convex lens. We observe the object which is very small and near to the lens which makes a virtual and magnified image of the object because object is placed between focus and lens. Hence statement 4 is correct.
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Feb 20, 2025