question_answer

In   the   following circuit, the value of charge on capacitor of capacity 5 \[\mu \] F will be

A)  4.5 \[\mu \]C   

B)  9.0 \[\mu \]C           

C)  7 \[\mu \]C            

D)  30 \[\mu \]C

Correct Answer: B

Solution :

 The equivalent circuit Total charge at capacitor of\[2.1\mu F\] \[q=2.1\times 6\] \[=12.6\times {{10}^{-6}}C\] \[=12.6\mu C\] Therefore\[3\mu F\]and\[7\mu F\]will have equal charges\[12.6\mu C\]each. The potential difference between plates of capacitor\[7\mu F=\frac{12.6}{7}=1.8V\] Therefore, charge on capacitor of capacity \[5\mu F\] \[=1.8\times 5\] \[=9\mu C\]