Question

total resistance of the given circuit is 2 ohms calculate r3 if R1 and R2 is 8ohm ​

Answer 1

V=12V

R1, R2 and R3 are connected in parallel.

(a) Current through R1 = V/R1 = 12/5 = 2.4 A

Current through R2 = V/R2 = 12/10 = 1.2 A

Current through R3 = V/R2 = 12/30 = 0.4 A

(b) Total current in the circuit = 2.4 + 1.2 + 0.4 = 4 A

(c) Total resistance in the circuit=R

1/R = 1/R1+ 1/R2 + 1/R

1/R = 1/5 + 1/10 + 1/30

1/R = 10/30

R = 3 ohm