Optics Question 911
Question: The image formed by a convex mirror of focal length $ 30cm $ is a quarter of the size of the object. The distance of the object from the mirror is
Options:
A) $ 30cm $
B) $ 90cm $
C) $ 120cm $
D) $ 60cm $
Show Answer
Answer:
Correct Answer: B
Solution:
$ m=\frac{f}{(f-u)}\Rightarrow ( +\frac{1}{4} )=\frac{(+30)}{(+30)-u}\Rightarrow u=-\ 90\ cm $
