(a) A student is unable to see clearly the words
written on the black board placed at a distance
of approximately 3 m from him. Name the
defect of vision the boy is suffering from. State
the possible causes of this defect and explain
the method of correcting it.
(b) Why do stars twinkle ? Explain.
Answers
Answered by
4
THE BOY IS SUFFERING FROM MYOPIA
CAUSES :-
1) EXCESSIVE CURVATURE OF EYE LENS
2) ELONGATION OF EYE BALLS
CORRECTION :-
USE OF CONCAVE LENS OF APPROPRIATE POWER.
THE AMOUNT OF LIGHT COMING FROM STARS ALSO VARY DUE TO CHANGE IN REFRACTIVE INDEX OF ATMOSPHERE
CAUSES :-
1) EXCESSIVE CURVATURE OF EYE LENS
2) ELONGATION OF EYE BALLS
CORRECTION :-
USE OF CONCAVE LENS OF APPROPRIATE POWER.
THE AMOUNT OF LIGHT COMING FROM STARS ALSO VARY DUE TO CHANGE IN REFRACTIVE INDEX OF ATMOSPHERE
Similar questions