A person may suffer from both myopia and hypermetropia defects. (a) What is this condition called? (b) When does it happen? (c) Name the type of lens often required by the persons suffering from this defect. Draw labelled diagram of such lenses.

A person is suffering from the defect of myopia. His far point will be:

A person is suffering from the defect astigmatism. Its main reason is

In old age, people often suffer from stiff and inflamed joints. What is this condition called? What are the possible reasons for these symptoms?

In old age, people often suffer from stiff and inflamed joints. What is this condition called? What are the possible reasons for these symptoms?

Due to gradual weakening of ciliary muscles and diminishing flexibility of the eye lens, a certain defect of vision arises. Write the name of this defect. Name the type of lens required by such persons to improve the vision. Explain the structure and function of such a lens.

A person is unable to see objects distinctly placed within 50 cm from his eyes. (a) Name the defect of vision the person is suffering from and list its two possible causes. (b) Draw ray diagram to show the defect in the above case. (c) Mention the type of lens used by him for the correction of the defect and calculate its power. Assume that the near point for the normal eye is 25 cm. (d) Draw a labelled diagram for the correction of the defect in the above case.

A person cannot see distinctly the book placed nearer than 60 cm from his eyes. (i) Name the defect of vision the person is suffering from. (ii) List two possible causes of this defect. (iii) Draw a ray diagram to show this vision defect. (iv) How can this defect be corrected ? (v) Draw a ray diagram to show the correction of this defect.

A person with 47 chromosomes due to an additional Y-chromosome suffers from a condition called

A person suffers from frequent urination feels thirsty and there is no glucose in the urine ,what may be the cause

We wish to obtain an equal sized inverted image of a candle flame on a screen kept at a distance of 4 m from the candle flame. (a) Name the type of lens that should be used. (b) what should be the focal length of the lens and at what distance from the candle flame the lens be placed ? (c) Draw a labelled diagram to show the image formation in this case.