Solve Question no. 61 TYPE
POWER ASSO
A.C. CIRCUITS, POWER FACTOR
57. An a-c. circuit containing 800 rnH inductor m.d
a 60 F capacitor is in series with IS ohm
resistance. *Ihey• are connected to 230 V, SO Hz
a-c. supply. Obtain average power transferred to
each element and total m»wer absorbed-
P=20-05watt1
SS. A group of electric bulbs have a power rating of
300 watt. An a-c. voltage V = 141.4 sin (314 t
+ z/3) is applied to the group. Calculate the
[Ans. 3 A1
effective current.
59. A 60 cycle AC circuit has a resistance of 200 Q
and inductance of 10 my-I. What is the power
factor ? What capacitance placed in the circuit
will make the power factor unity ?
[Ans. 0.99, 703 Fl
60. Find the capacity of a capacitor, which when put
in series with a 10 ohm resistor, makes the power
factor equal to 06. Assume an 80 V—IOO Hz a-c.
[Ans. 9-2 x 10-5 F]
supply.
61. Calculate the value of an inductance, which
should be connected in series with a capacitance
of 5 g F and a resistance of 10 ohm and a-c. source
of 50 hz, so that the power factor of the circuit i
[Ans. 2-028 H'.
62. An LCR series circuit with 100 Q resistance i
connected to an a-c. source of 200 V and angul-