Q.181 Consider a RL series circuit, the current ____
A. lags the applied voltage by 0° to 180°
B. lags the applied voltage by 0° to 90°
C. leads the applied voltage by 0° to 90°
D. lags the applied voltage by 45° to 90°
Ans.: B
Q.182 which of the following expression is correct for impedance of RL series circuit?
A. Z = R+jX
B. Z = R+j0
C. Z = R-jX
D. Z = R+jXL
Ans.: D
Q.183 The impedance can be expressed as
A. Z = jX
B. Z = R+jX
C. Z = R+X
D. Z = R-jX
Ans.: B
Q.184 The expression of instantaneous power in ac circuit is given by
A. p = v x i
B. p = VI
C. p = v x i cosф
D. P = VmIm sinф
Ans.: A
Q.185 Consider a circuit which takes a current of 8 A at 100V and current is lags behind the applied voltage by 30°. Find out impedance and inductance.
A. 125Ω and 19.9Ω
B. 12.5Ω and 199Ω
C. 12.5Ω and 19.9Ω
D. 1.25Ω and 1.99Ω
Ans.: C
Q.186 what is unit of inductive susceptance?
A. Siemens
B. ohms
C. Henry
D. Farad
Ans.: A
Q.187 In ac circuit power is consumed
A. only in capacitance
B. only in inductance
C. only in resistance
D. all of the above
Ans.: C
Q.188 A 220 V bulb is connected to 220 V , 5 Hz source. What will happen?
A. Bulb glow intermittently
B. bulb damaged
C. does not glow
D. Constantly glow
Ans.: A
Q.189 what is unit of capacitive susceptance?
A. ohms
B. Siemens
C. Weber
D. ohms per meter
Ans.: B
Q.190 The ability of purely capacitive circuit to pass current is called___
A. capacitive susceptance
B. capacitive reactance
C. Capacitance
D. Impedance due to capacitor
Ans.: A
Q.191 Find voltage across R and L if a series circuit of R= 20 ohms and L = 20 mH and supply is 60 V with 100 Hs.
A. 50.8 V and 31.9 V
B. 5.08 V and 3.19 V
C. 31.9 V and 50.8 V
D. 51.8 V and 32.9 V
Ans.: A
Q.192 which of the following is reciprocal of impedance?
A. capacitance
B. Admittance
C. inductance
D. reactance
Ans.: B
Q.193 The unit of admittance is ___
A. mho
B. Farad
C. Siemens
D. ohm per meter
Ans.: C
Q.194 In ideal capacitor and inductor has ____.
A. resistance and dissipates energy
B. no resistance and no energy is dissipated
C. only resistance and no energy is dissipated
D. no resistance and dissipates energy
Ans.: B
Q.195 In practical L, dissipates of energy is due to
A. its winding resistance
B. due to hysteresis losses
C. due to eddy current losses
D. Both a and B
Ans.: D