Question

Distance between F1 and F2 is 20 cm. Find the power of the convex lens​ ?​

Answer 1

Answer:

it would be great if they mentioned about the focal length

Explanation:

it's formula based

Answer 2

The power of the convex lens is (F1+F2+20)/F1xF2

Explanation:

• there is a formula for determination of power when there are two different lenses which are separated by a particular  distance.
• The resultant power of the  lens which is produced by the combination =

$\frac{1}{F1} +\frac{1}{F2} + \frac{d}{F1F2}$

= $\frac{F1+F2+20}{F1F2}$

This formula is useful for finding the the effective power of lens when they are used in combination along with each other. This formula can be derived by the  use of lens formula