Electrical Engineering - Parallel Circuits - Discussion

Total Resistance=50
R1 and R2 are in parallel.
(1/R1)+(1/R2)=(1/50)
R1=270 ohms (given)
R2=61.36
R2=R1/(m-1)
where m=(Total Current/Current through 270 ohms)
Using above formula find out the current through 270 ohms...

Concept of raja and ramesh wrong, Sehegal is correct.
Try this way:
Total voltage = 50ohm * 120mA = 6 V
Current through 270 ohm resistor = 6 V/270 ohm = 22 mA

R1 and R2 are in parallel,

So (R1) * (R2) / (R1+R2) =50.

R1 = 270 ohm, R2 is unknown.

We get R2 = 61. 3 ohms.

Now using current division rule we get,

I2 = (Total current) * (R2/R1+R2).

= 120* (61/331).

= 22 mA.

That is the required answer, hope you people understand.

Ri = 50ohm.

Ii = 120 mA = 0.120A.

R1 = 270 ohm.

U = Ii*Ri = 0.120*50 = 6V.

I1 = U/R1 = 6/270 = 0.022A = 22 mA.

@Abd.

This method can be used as you have the total resistance as 50 ohm and total current as 120 mA given.

Voltage division For Series Circuits.
Vr = (R/Req) * V.

Current Division for parallel circuit
Ir = (Req/R) * I.

Where Req is the equivalent resistance (either series or parallel.
R is the resistance for which you want to determine the voltage or current.
Ir and Vr are the current and voltage respectively of the resistor in question.
I and V are the current and voltage respectively to be divided.