Electronics - RL Circuits - Discussion
Discussion Forum : RL Circuits - General Questions (Q.No. 3)
3.
What is the true power of a 24 Vac parallel RL circuit when R = 45
and XL = 1100
?


Discussion:
12 comments Page 1 of 2.
Sindhu priya said:
1 decade ago
I=V/R=24/45=0.533
P=VI=24*0.533=12.8
P=VI=24*0.533=12.8
(4)
Rajan said:
9 years ago
Another way is total I * V.
There is a power dissipated in the resistor and also low lost in Inductor.
So both need to be considered !
In parallel circuit Total current It= IL +Ir but since they are not in the same phase so cannot plus directly.
It^2 = IL^2 + Ir^2.
Ir = V/R =24/45 = 0.533.
IL = V/Xl =24/1100 = 0.0218.
It = sqr(IL^2 +Ir^2) = sqr(0.5333*0.5333 +0.02182*0.02182) = 0.53345.
It = 0.53345 ampere.
Power = VIt = 24 * 0.5334 = 12.80 (more accurate).
There is a power dissipated in the resistor and also low lost in Inductor.
So both need to be considered !
In parallel circuit Total current It= IL +Ir but since they are not in the same phase so cannot plus directly.
It^2 = IL^2 + Ir^2.
Ir = V/R =24/45 = 0.533.
IL = V/Xl =24/1100 = 0.0218.
It = sqr(IL^2 +Ir^2) = sqr(0.5333*0.5333 +0.02182*0.02182) = 0.53345.
It = 0.53345 ampere.
Power = VIt = 24 * 0.5334 = 12.80 (more accurate).
(1)
Ranjit said:
1 decade ago
No power is dissipated in L...
So P=(Vpow2)/R
So P=(Vpow2)/R
Soundarya said:
1 decade ago
There is no dissipation of power at inductor.so
p=v^2/R
=(24*24)/45=12.8 is the answer
p=v^2/R
=(24*24)/45=12.8 is the answer
C.P. BORKAR said:
1 decade ago
First calculate
I=V/R =24/45 = O.533
THEN P=VI
P=24*0.533
P=12.8
I=V/R =24/45 = O.533
THEN P=VI
P=24*0.533
P=12.8
Hareshwar said:
1 decade ago
Good answer.
Lochana.vyas said:
1 decade ago
As they said only true power so inductance value will not be there and only purely resistive load is used:-.
V^2/R = (24) ^2/45 = 12.8W.
V^2/R = (24) ^2/45 = 12.8W.
Nasim said:
1 decade ago
Please say why there is no power dissipation in the inductor?
ARUN said:
1 decade ago
Impedance z = 44.9 ohm.
I = V/Z = 0.534 A.
TRUE POWER = V*I*COS(PHI)=12.78 VOLT.
PHI = TAN inv(R/Xl) = 2.34.
I = V/Z = 0.534 A.
TRUE POWER = V*I*COS(PHI)=12.78 VOLT.
PHI = TAN inv(R/Xl) = 2.34.
Sudhi. said:
1 decade ago
If there is no losses in the inductor it is simple. This means no equivalent series or parallel are. Use 2pi x f x L to get the reactance, and then the current by ohms law.
There is no power dissipated. Current is drawn but it recirculates without any heating. The inductor charges and discharges.
There is no power dissipated. Current is drawn but it recirculates without any heating. The inductor charges and discharges.
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