Electrical Engineering - RL Circuits - Discussion
Discussion Forum : RL Circuits - General Questions (Q.No. 1)
1.
A 1.5 k
resistor and a coil with a 2.2 k inductive reactance are in series across an 18 V ac source. The power factor is
resistor and a coil with a 2.2 k inductive reactance are in series across an 18 V ac source. The power factor isDiscussion:
20 comments Page 1 of 2.
Pavan said:
2 years ago
@All.
The main simple thing we need to see here is the power factor should not be greater than 1.
The main simple thing we need to see here is the power factor should not be greater than 1.
(3)
Siddharth said:
7 years ago
Power factor = R ÷ Z.
So, R = 1.3k ohm = 1.3 * 10^3 =1300 ohm,
inductive reactians FL = 2.2k ohm =2.2 * 10^3,
= 2200 ohm.
&. Z = (?).
Z = √(R^2 + FL^2),
Z = √(1500^2 + 2200^2),
Z= 2663.
& Power factor = R ÷ Z,
= 1500 ÷ 2663,
= 0.5632.
So, ans is (0.564).
So, R = 1.3k ohm = 1.3 * 10^3 =1300 ohm,
inductive reactians FL = 2.2k ohm =2.2 * 10^3,
= 2200 ohm.
&. Z = (?).
Z = √(R^2 + FL^2),
Z = √(1500^2 + 2200^2),
Z= 2663.
& Power factor = R ÷ Z,
= 1500 ÷ 2663,
= 0.5632.
So, ans is (0.564).
(3)
VENKATESH said:
1 decade ago
R = 1.5.
Xl = 2.2.
Z = Root of R square+xl square.
Cos = R/Z.
Xl = 2.2.
Z = Root of R square+xl square.
Cos = R/Z.
(1)
Kalyan G said:
6 years ago
Z=(r^2+XL^2)^1/2=2663.
P.f = cosq = r/z
0.564.
P.f = cosq = r/z
0.564.
(1)
Arpana singh said:
7 years ago
R/Z=0.405 not 0.564.
(1)
Vicky said:
9 years ago
cos(q) can never be greater than 1.
(1)
Shenoy said:
1 decade ago
Power factor always less than 1 use common sense, so simple.
(1)
Noel Zamora said:
1 decade ago
tan 2.2/1.5 = 1.4667, arc tan 1.4667 = 55.71 deg.,
Therefore cos 55.71 deg. = 0.564 or pf = 0.564(lagging).
Therefore cos 55.71 deg. = 0.564 or pf = 0.564(lagging).
Hadiro tafoua said:
1 decade ago
Using all method above we get close intervals of answers. Since it all corresponds to electric quantities.
Shaila kedar said:
1 decade ago
Power factor is always less than 1.
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