Electrical Engineering - Parallel Circuits - Discussion

Whatever may be a count of the resistance in parallel.
That's not important here ...

here, they were given total resistance and total voltage and all the resistance is connected in parallel.
Let's make it simple..voltage across each resistance is the same (because of the parallel circuit)

Total voltage = voltage drop in anyone of the resistance part.

Total current * Total resistance = Individual current* particular resistance value,
50 *120 = x *270.
X = (50 *120)/270.
X ~ 22mA.

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.

I think we can do by ohm's also. In first case we know resistance value and current by this we can find voltage value. In second case we we know resistance value and we already find voltage in first case by using these we can find current.

Ex : Case 1:

V = IR.
V = 50*120 ma.
V = 6 volt.

Case 2:

I = v/r.
I = 6/270.
I = 22 ma.

Let me know this method is correct or not.

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.

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...

As the resistances are in parallel so,
Req = R1 * R2/(R1+R2).
So from here, 50 = 270 * R2/(270+R2).
R2=61.3ohm.
Now, using the current division rule for I, we get;
I2 = I * (R2/R2+R1).
I2 = 22ma.

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

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.

According to current div rule.

Current= (total current*total resistance) /particular resistance.