An object placed on the principle axis of a convex lens o...
An object placed on the principle axis of a convex lens of focal length 10m produces a real image of double magnification. The image distance from the lens is
30cm
25cm
20cm
15cm
10cm
Correct answer is A
1v + 1u = 1f
1v = +ve real image distance
where; U = +ve real object distance
f = real focus = 10
m = magnification
M = 2 = vu
2u = V
12u + 1u = 110
2u = 30
u = 15cm
v = 2u = 2 x 15
= 30cm