A person wears spectates with concave lenses. It means that normally (when not using glasses), the image of distant objects is focused in his eyes:

Related Mcqs:

1. A convex lens gives a virtual image only when the objects lies_________________?

   A. between principal focus and center of curvature
   B. beyond 2 f
   C. at the principal focus
   D. between principal focus and optical center

2. Two convex lenses of equal focal length f are placed in contact the resultant focal length of the combination is______________?

   A. zero
   B. focus
   C. 2 f
   D. f/2

3. The power of a concave lens is_______________?

   A. real
   B. virtual
   C. positive
   D. negative

4. A convex lens of focal length f1 and a concave lens of focal length f2 are placed in contact. The focal length of the combination is_____________?

   A. f2 + f1
   B. f2 – f1
   C. f1f2/f2+f1
   D. f1f2/f1-f2

5. Dioptre power of an concave lens of 10 cm focal length is_______________?

   A. 10 dioptre
   B. 10 dioptre
   C. 1 / 10 dioptre
   D. 1 / 10 dioptre

6. A three-dimensional image is obtained by________________?

   A. Electron microscope
   B. Scanning electron microscope
   C. Magnetic imaging
   D. None of the above

7. If an object is placed away from 2f of a converging lens then the image will be_______________?

   A. real and erect
   B. virtual and erect
   C. real and inverted
   D. virtual

8. Final image produced by a compound microscope is_____________?

   A. real and inverted
   B. real and erect
   C. virtual and erect
   D. virtual and inverted

9. Image of an object 5 mm high is only 1 cm high. Magnification produced by lens is__________________?

   A. 0.5
   B. 0.2
   C. 1
   D. 2

10. The minimum distance between an object and its real image in a convex lens is_____________?

    A. 2 f
    B. 2.5 f
    C. 3f
    D. 4f