A) \[\frac{R}{{{\mu }_{1}}-{{\mu }_{2}}}\]
B) \[\frac{2R}{{{\mu }_{1}}-{{\mu }_{2}}}\]
C) \[\,\frac{R}{2\left( {{\mu }_{1}}-{{\mu }_{2}} \right)}\]
D) \[\,\frac{R}{2-\left( {{\mu }_{1}}+{{\mu }_{2}} \right)}\]
Correct Answer: A
Solution :
[a] \[\frac{1}{F}=\frac{1}{{{f}_{1}}}+\frac{1}{{{f}_{2}}}\] \[\frac{1}{F}=\left( {{\mu }_{1}}-1 \right)\left( \frac{1}{\infty }+\frac{1}{R} \right)+\left( {{\mu }_{2}}-1 \right)\left( \frac{1}{-R}-\frac{1}{\infty } \right)\] \[=\frac{{{\mu }_{1}}-{{\mu }_{2}}}{R}\] \[F=\frac{R}{{{\mu }_{1}}-{{\mu }_{2}}}\]You need to login to perform this action.
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