Question

A man can read a book kept at a distance of 20 cm. If book kept at 30 cm distance,
man uses spectacles to read this book. Calculate-(i) focal length of used lens,
(ü) nature of lens, (iii) clarify the defect of vision by drawliny rag diagram.​

Answer 1

Answer:

(i) 10 cm.

(ii) concave lens.

(iii) (it's in photo)

Explanation:

(i) 20+30= not able to read,

30-20=10=difference between able to read. and not able to read.

(ii) concave lens make smaller objects to look big.

(iii) please make my ans. as brilliant ans. please.

Answer 2

Answer:

Given, u = -20 cm, v = - 30 cm , P = ?

Explanation:

Given, u = -20 cm, v = - 30 cm , P = ?