Question

in a circuit diagram how to find I1,I2and I3 if R1=2ohm ,R2=3ohm ,R3=6ohm​

Answer 1

r1 = 5 \: ohm \:

r2 = 10 \: ohm

r3 = 30 \: ohm

Current through R1,

i1 = \frac{v}{r1} = \frac{12}{5} = 2.4 \: a

Current through R2,

i2 = \frac{v}{r2} = \frac{12}{10} = 1.2 \: a

Current through R3,

i3= \frac{v}{r3} = \frac{12}{30} = 0.4 \: a

Total current across the circuit is the sum of of all currents flowing through the individual resistors.

i = i1 + i2 + i3 = 2.4 + 1.2 + 0.4 = 4 \: a

Equivalent resistance across the parallel combination is,

\frac{1}{r} = \frac{1}{r1} + \frac{1}{r2} + \frac{1}{r3} = \frac{1}{5} + \frac{1}{10} + \frac{1}{30} = \frac{1}{3}

r = 3 \: ohm