Question

Two batteries A and B having e.m.fs. 12 V and 8 V respectively and internal resistances of 2 Q and 10 respectively, are connected in parallel across 10 Q resistor. Calculate (i) the current in each of the batteries and the external resistor and (ii) p.d. across external resistor.​

Answer 1

Answer:

Equivalent resistance of r

1

and r

2

, r

eq

=

1+2

1×2

=0.66Ω

Equivalent emf of E

1

and E

2

, E

eq

=[

r

1

E

1

+

r

2

E

2

]r

eq

⟹ E

eq

=[

1

12

+

2

13

]×0.66=12.33 V

Potential across R, V

R

=

R+r

eq

R

E

eq

⟹ V

R

=

10+0.66

10

×12.33=11.57 V