Optics Question 796
Question: A cube of side 2 misplaced in front of a concave mirror of focal length 1m with its face P at a distance of 3 m and face Q at a distance of 5 m from the mirror. The distance between the image efface P and Q is
Options:
A) 1m
B) 0.5m
C) 0.5m
D) 025m
Show Answer
Answer:
Correct Answer: D
Solution:
[d] For $ P:\frac{1}{v}+\frac{1}{u}=\frac{1}{f} $
$ \text{or }\frac{1}{v _{P}}+\frac{1}{-3}=\frac{1}{-1}\text{ or }{{v} _{P}}=-\frac{3}{2}m $
For $ Q:\frac{1}{v _{Q}}+\frac{1}{-5}=\frac{1}{-1}\text{ or }v _{Q}=\frac{-5}{4}m $
So horizontal distance between image of P and Q is 0.25m
