A) \[\frac{M}{4}\]
B) \[3M\]
C) \[2M\]
D) \[4M\]
Correct Answer: C
Solution :
Key Idea: Minimum magnifying power is equal to ratio of focal length of objective to that of eyepiece. Magnifying power M is given by \[M=\frac{{{f}_{0}}}{{{f}_{e}}}\] where\[{{f}_{0}}\]is focal length of objective, and \[{{f}_{e}}\]is focal length of eyepiece. Given, \[f_{e}^{}=\frac{{{f}_{e}}}{2}\] \[\ \therefore \] \[M=\frac{{{f}_{0}}}{{{f}_{e}}/2}=2.\frac{{{f}_{0}}}{{{f}_{e}}}=2M\]You need to login to perform this action.
You will be redirected in
3 sec