Question

SECTION D
Answer the following Questions (FIVE Marks Each)
38. Three capacitors of capacitance 2,3 and 6 microfarads are charged by a 60 V battery.Find the energy stored when
the capacitors are charged when connected in series and parallel.
39 If there are 18 cells in

Answer 1

Answer:

Given :          C  

1

​  

=3μF                 C  

2

​  

=6μF                    C  

3

​  

=6μF

Equivalent capacitance for series combination              

C  

eq

​  

 

1

​  

=  

C  

1

​  

 

1

​  

+  

C  

2

​  

 

1

​  

+  

C  

3

​  

 

1

​  

           

     

C  

eq

​  

 

1

​  

=  

3

1

​  

+  

6

1

​  

+  

6

1

​  

      ⟹C  

eq

​  

=1.5μF            

Thus the charge flowing through the circuit         q=C  

eq

​  

V

q=1.5μF×120 volt  =180μC

Potential difference across  3μF,            V  

1

​  

=  

C  

1

​  

 

q

​  

=  

3μF

180μC

​  

=60 volt