To obtain a magnification of 2.5, how far should an object be placed from the pole of a thin converging lens of focal length 10.20m?
- 0.13m
- 0.25m
-
0.28m
- 0.50m
The correct answer is: C
Explanation
v = 2.5uF = \(\frac {uv}{u + v}\)
0.2 = \(\frac {u \times 2.5u}{u + 2.5u}\)
u = 0.28m