Question

(a) If a person wears lens of power -6 D for distant vision and for correcting his near vision he
needs a lens of +2 D. Determine the focal length of the lenses in both the case.?
(b) Give reason for the following natural phenomenon :
(i) Objects behind the fumes appear to be wavering.
(ii) Planets do not twinkle.



answer plz​

Answer 1

Answer:

GIVEN

A PERSON WEARS LENS OF POWER -6

HE NEEDS A +2D LENS

THEN THE FORCAL LENGTH 1/F= POWER OF THE LENS

THE P= -6+2

P=4

THEN FORCAL LENGTH IS 1/F=4

F=4m

object behind fumesappear to be wavering because it is an optical phenomenon of total internal reflectiom and its is approximately equal to the explanation of mirage

plants dont twinkle because plants contain atmoshpere