Question

A circuit is having 3 resistors 2 ohm, 4 ohm and 8 ohm. 2 ohm and 4 ohm are connected in

series and the equivalent of these resistors ( 2 ohm and 4 ohm ) is connected in parallel with 8

ohm across a 12 V battery. Find

(i) Equivalent Resistance of the circuit

(ii) Current through 2 ohm, 4 ohm and 8 ohm resistors

(iii)Voltage drop across 2 ohm, 4 ohm and 8 ohm resistors. ​

Answer 1

Explanation:

(i) Re = 4+2 ohm = 6 ohms

now , for parallel combination

1/Re = 1/6 + 1/8 = 7/24 ohms

Re = 24/7 = 3.428 ohms

(ii) 2 ohm and 4 ohm resistors are connected in series,so equal current would flow through them

I= V/R = 12/ (2+4)

I= 2A

and I for 8 ohms resistor

I= 12/8 = 1.5A

(iii) As 8 ohm resistor is connected in parellel so it would have same voltage as of battery = 12 V

V = IR = 2 * 2 = 4V

V = IR = 2*4= 8V