Question

Two cells of emf 1.5v and 2v having internal resistance 0.2 and 0.3 ohm

Answer 1

Answer:

Explanation:

E  

1

​  

=1.5V            E  

2

​  

=2.0V             r  

1

​  

=0.2Ω               r  

2

​  

=0.3Ω

Equivalent resistance of parallel combination :              

r  

eq

​  

 

1

​  

=  

r  

1

​  

 

1

​  

+  

r  

2

​  

 

1

​  

 

∴      

r  

eq

​  

 

1

​  

=  

0.2

1

​  

+  

0.3

1

​  

=  

0.2×0.3

0.2+0.3

​  

 

⟹   r  

eq

​  

=0.12Ω

Equivalent Emf           E  

eq

​  

=[  

r  

1

​  

 

E  

1

​  

 

​  

+  

r  

2

​  

 

E  

2

​  

 

​  

]r  

eq

​  

 

∴E  

eq

​  

=[  

0.2

1.5

​  

+  

0.3

2.0

​  

]×0.12  

E  

eq

​  

=[7.5+6.67]×0.12=1.7V