1. . When two AC waves having the same frequency start & finish from the same point collectively then these are called:
(A) Phase
(B) Out of phase
(C) In-phase
(D) None
2. . The line which has specific direction and length is called:
(A) Scalar
(B) Vector
(C) Phasor
(D) Both b & c
3. . The waveform which is behind the other waveform w.r.t time or angle is called:
(A) Lagging wave
(B) Leading wave
(C) Anti phase wave
(D) Phase quadrature wave
4. . The waveform which is ahead of the other waveform w.r.t. time or angle is called:
(A) Lagging wave
(B) Leading wave
(C) Anti phase wave
(D) Phase quadrature wave
5. . Formula to find the impedance of the RC series circuit is:
(A) Z = √(R² + XL²)
(B) Z = V ÷ I
(C) Z = Cosφ
(D) Z = √(R² + XC²)
6. . The unit of impedance is:
(A) Henry
(B) Ohm
(C) Ohm/m
(D) Henry/m
7. . In the impedance triangle, the base indicates:
(A) XL
(B) Impedance
(C) Resistance
(D) XL – R
8. . In the impedance triangle, the hypotenuse indicates:
(A) XL
(B) Impedance
(C) Resistance
(D) XL – R
9. . In the purely resistive circuit, the current & voltage are:
(A) On 180°
(B) On 90°
(C) Out of phase
(D) In phase
10. . The phase angle of the purely resistive circuit is:
(A) 0°
(B) 30°
(C) 60°
(D) 90°
11. . Power factor of the purely resistive circuit is:
(A) 0
(B) 0.5
(C) 0.8
(D) Unity
12. . Current lags with voltage in a purely inductive circuit:
(A) 0°
(B) 0–90°
(C) 90°
(D) 120°
13. . Phase angle between V & I in a purely inductive circuit:
(A) 30°
(B) 60°
(C) 90°
(D) In phase
14. . In the purely inductive circuit, current _______ with voltage:
(A) Leads
(B) Lags
(C) In-phase
(D) None
15. . In the purely inductive circuit, the formula to find the power is:
(A) P = VI
(B) P = I²R
(C) P = V² / R
(D) P = VI cos φ
16. . Power consumed in the purely inductive circuit is:
(A) 0
(B) Low
(C) Medium
(D) Maximum
17. . The unit of XL is:
(A) Henry
(B) Henry/m
(C) Ohm/m
(D) Ohm
18. . Formula to determine the current in a purely inductive circuit is:
(A) I = V/R
(B) I = V/XL
(C) I = V/Z
(D) All
19. . Formula to determine voltage in the purely inductive circuit is:
(A) V = IR
(B) V = I XL
(C) V = I Z
(D) All
20. . In the pure capacitive circuit, the current & voltage are:
(A) On 0°
(B) 0–90°
(C) On 90°
(D) 120°
21. . Current ______ with voltage in the pure capacitive circuit:
(A) Leads
(B) Lags
(C) In-phase
(D) None
22. . The power factor of a purely capacitive circuit is:
(A) 0
(B) 0.707
(C) 0.636
(D) Unity
23. . In the capacitive circuit, with increasing the frequency, XC is:
(A) Increased
(B) Decreased
(C) Constant
(D) Zero
24. . In the capacitive circuit, the formula for XC is:
(A) XC = 2πfC
(B) XC = 1/(2πfC)
(C) XC = 2πfL
(D) XC = I/V
25. . The unit of XC is:
(A) Ohm
(B) Henry
(C) Henry/m
(D) Ohm/m
26. . In the RL series circuit, current & voltage are:
(A) In phase
(B) Current 90° lags
(C) Voltage 90° lags
(D) Current lags between 0° & 90°
27. . In the RL series circuit, the actual component of voltage is:
(A) V cos φ
(B) V sin φ
(C) V tan φ
(D) VI sin φ
28. . In the RC series circuit, current & voltage are:
(A) In phase
(B) Current leads 90°
(C) Current lags 90°
(D) Current leads between 0° & 90°
29. . In a series RLC circuit, phase difference between the current in capacitor & resistor is:
(A) 0°
(B) 90°
(C) 180°
(D) 360°
30. . In a series RLC circuit, phase difference between the current in inductor & resistor is:
(A) 0°
(B) 90°
(C) 180°
(D) 360°
31. . In a series RLC circuit, phase difference between the current in the circuit & voltage across resistor is:
(A) 0°
(B) 90°
(C) 180°
(D) 360°
32. . In a series RLC circuit, phase difference between the current & voltage across capacitor is:
(A) 0°
(B) 90°
(C) 180°
(D) 360°
33. . Voltage across capacitor & inductor are:
(A) In phase
(B) 180° out of phase
(C) 90° out of phase
(D) 45° out of phase
34. . Method to solve RLC parallel circuit:
(A) Vector method
(B) Admittance method
(C) Phasor algebra
(D) All
35. . Above the resonant frequency, current in inductor ______ voltage in series RLC:
(A) Lags
(B) Below
(C) Equal
(D) Depends
36. . In RLC circuit, when XL = XC then it is called:
(A) Impedance
(B) Resonance
(C) Conductance
(D) Susceptance
37. . As XL = XC in series resonance, impedance is:
(A) Purely capacitive
(B) Purely inductive
(C) Purely resistive
(D) Capacitive & inductive
38. . In parallel resonance, circuit impedance is:
(A) C ÷ LR
(B) R ÷ LC
(C) CR ÷ L
(D) L ÷ CR
39. . Resonant circuit contains ______ elements:
(A) R & L only
(B) R & C only
(C) Only R
(D) L & C
40. . Series RLC above resonance, current:
(A) Lags applied voltage
(B) Leads applied voltage
(C) In phase with voltage
(D) Zero