If the magnification of a virtual image formed by an obje...
If the magnification of a virtual image formed by an object 10cm from a convex less is 3, then the focal length of the lens is
10cm
20cm
25cm
15cm
Correct answer is D
M = vu = 3 = v30. V = 30m
1u + 1v = 1f = 110 - 130 = 1f
3−130 = 1ff=\(302 = 15cm