The r.m.s. value of a sinusoidal A.C. current is equal to its value at an angle of_______degrees?

Related Mcqs:

1. If a sinusoidal wave has frequency of 50 Hz with 30 A r.m.s. current which of the following equation represents this wave_________ ?

   A. 42.42 sin 3141
   B. 60 sin 25 t
   C. 30 sin 50 t
   D. 84.84 sin 25 t

2. What will be the phase angle between two alternating waves of equal frequency, when one wave attains maximum value the other is at zero value________ ?

   A. 0°
   B. 45°
   C. 90°
   D. 180°

3. The product of apparent power and cosine of the phase angle between circuit voltage and current is

   A. true power
   B. reactive power
   C. volt-amperes
   D. instantaneous power

4. The square waveform of current has following relation between r.m.s. value and average value?

   A. r.m.s. value is equal to average value
   B. r.m.s. value of current is greater than average value
   C. r.m.s. value of current is less than average value
   D. none of the above

5. The peak value of a sine wave is 200 V. Its average value is___________?

   A. 127.4 V
   B. 141.4 V
   C. 282.8 V
   D. 200V

   Updated by: Ihtisham Ul Haq

6. The r.m.s. value of alternating current is given by steady (D.C.) current which when flowing through a given circuit for a given time produces__________?

   A. the more heat than produced by A.C. when flowing through the same circuit
   B. the same heat as produced by A.C. when flowing through the same circuit
   C. the less heat than produced by A.C. flowing through the same circuit
   D. none of the above

7. In series resonant circuit, increasing inductance to its twice value and reducing capacitance to its half value__________?

   A. will change the maximum value of current at resonance
   B. will change the resonance frequency
   C. will change the impedance at resonance frequency
   D. will increase the selectivity of the circuit

8. Two waves of the same frequency have opposite phase when the phase angle between them is_________?

   A. 360°
   B. 180°
   C. 90°
   D. 0°

9. For the same peak value, which of the following wave has the least mean value ?

   A. half wave rectified sine wave
   B. triangular wave
   C. sine wave
   D. square wave

10. The r.m.s. value and mean value is the same in the case of___________?

    A. triangular wave
    B. sine wave
    C. square wave
    D. half wave rectified sine wave