34. A storage battery of e.m.f. 12.0 V and internal
resistance 0.5 12 is to be charged by a 120V
d.c. supply of negligible internal resistance
What resistance is required in the circuit for
the charging current to be 3 A ? What is the
terminal voltage of the battery during
charging?
Answers
Answered by
7
Solution :-
As per the given data ,
- EMF(E) = 12 V
- Internal resistance (r) = 0.5 Ω
- Current flowing through the circuit (I) = 3 A
- Voltage of the DC supply(V) = 120 V
(1)
As per the formula ,
➜ I = (V-E) ÷ (R +r)
Now let's substitute the given values in the above equation ,
➜ 3 = 120 - 12 / R + 0.5
➜ 3 R + 1.5 = 108
➜ 3R = 108 - 1.5
➜ 3R = 106.5
➜ R = 106.5 / 3
➜ R = 35.5 Ω
The resistor required to provide a charging current of 3 A is 35.5 Ω.
(2)
➜ Terminal voltage = E - I r
➜ Terminal voltage = 12 - 3 x 0.5
➜ Terminal voltage = 12 - 1.5
➜ Terminal voltage = 10.5 V
The terminal voltage of the battery during charging is 10.5 V
Similar questions