English
Karnataka Board PUCPUC Science Class 11

A Man Wearing Glasses of Focal Length +1 M Cannot Clearly See Beyond 1 M - Physics

Advertisements
Advertisements

Question

A man wearing glasses of focal length +1 m cannot clearly see beyond 1 m

Options

  • if he is farsighted

  • if he is nearsighted

  • if his vision is normal

  • in each of these cases

MCQ

Solution

 in each of these cases

The man is wearing glasses of positive power (converging lens). Hence, he cannot see nearby objects clearly. In other words, he is farsighted. Since he cannot see beyond 1 m, he is nearsighted. If a person with normal vision wears glasses of focal length +1 m, then the person will not be able to see beyond 1 m.

shaalaa.com
Optical Instruments: the Eye
  Is there an error in this question or solution?
Chapter 19: Optical Instruments - MCQ [Page 431]

APPEARS IN

HC Verma Concepts of Physics Vol. 1 [English] Class 11 and 12
Chapter 19 Optical Instruments
MCQ | Q 8 | Page 431

RELATED QUESTIONS

For a normal eye, the far point is at infinity and the near point of distinct vision is about 25cm in front of the eye. The cornea of the eye provides a converging power of about 40 dioptres, and the least converging power of the eye-lens behind the cornea is about 20 dioptres. From this rough data estimate the range of accommodation (i.e., the range of converging power of the eye-lens) of a normal eye.


Does short-sightedness (myopia) or long-sightedness (hypermetropia) imply necessarily that the eye has partially lost its ability of accommodation? If not, what might cause these defects of vision?


A myopic person has been using spectacles of power −1.0 dioptre for distant vision. During old age, he also needs to use the separate reading glass of power + 2.0 dioptres. Explain what may have happened.


A person looking at a person wearing a shirt with a pattern comprising vertical and horizontal lines is able to see the vertical lines more distinctly than the horizontal ones. What is this defect due to? How is such a defect of vision corrected?


What should be the distance between the object and the magnifying glass if the virtual image of each square in the figure is to have an area of 6.25 mm2. Would you be able to see the squares distinctly with your eyes very close to the magnifier?


The angle subtended at the eye by an object is equal to the angle subtended at the eye by the virtual image produced by a magnifying glass. In what sense then does a magnifying glass provide angular magnification?


In viewing through a magnifying glass, one usually positions one’s eyes very close to the lens. Does angular magnification change if the eye is moved back?


A Cassegrain telescope uses two mirrors as shown in the figure. Such a telescope is built with the mirrors 20 mm apart. If the radius of curvature of the large mirror is 220 mm and the small mirror is 140 mm, where will the final image of an object at infinity be?


The muscles of a normal eye are least strained when the eye is focussed on an object


When objects at different distances are seen by the eye, which of the following remain constant?


The focal length of a normal eye-lens is about


Can virtual image be formed on the retina in a seeing process?


A myopic adult has a far point at 0.1 m. His power of accomodation is 4 diopters.

  1. What power lenses are required to see distant objects?
  2. What is his near point without glasses?
  3. What is his near point with glasses? (Take the image distance from the lens of the eye to the retina to be 2 cm.)

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×