Question

a convex lens forms An erect image of an object placed at a distance of 15 cm from it. if the image formed is twice as big as the object find the :-
1) position of the object
2) focal length of the lens ​

Answer 1

Answer:

focal length will be +30 cm

Explanation:

given that hi=2 ho

therefore hi/ho = v/u

putting values

2 ho/ho = v/-15

v = -30 cm

therfore image is virtual

using 1/f = 1/v - 1/u

therefore f=+30 cm

hope it helps

pls mark braunliest