An object of heights 5 cm is placed at 20 cm from a concave mirror of focal length 10 cm. the image height is?
- 20 cm
- 15 cm
- 10 cm
-
5 cm
The correct answer is: D
Explanation
(1)/V + (1)/U = (1)/f
(1)/V + (1)/20 = (1)/10
(1)/V = (1)/10 - (1)/20 = (2 -1)/20 = (1)/20
∴ V = 20 cm
mag = (image height)/object height = (v)/u
(X)/5 = (20)/50
X = 5 cm
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