The r.m.s. value of pure cosine function is_________?

Related Mcqs:

1. 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

2. An A.C. voltage is impressed across a pure resistance of 3.5 ohms in parallel with a pure inductance of impedance of 3.5 ohms?

   A. the current through the resistance is more
   B. the current through the resistance is less
   C. both resistance and inductance carry equal currents
   D. none of the above

3. The safest value of current the human body can carry for more than 3 second is_________?

   A. 4 mA
   B. 9 mA
   C. 15 mA
   D. 25 mA

4. In a pure resistive circuit__________?

   A. current lags behind the voltage by 90°
   B. current leads the voltage by 90°
   C. current can lead or lag the voltage by 90°
   D. current is in phase with the voltage

5. In a pure inductive circuit___________?

   A. the current is in phase with the voltage
   B. the current lags behind the voltage by 90°
   C. the current leads the voltage by 90°
   D. the current can lead or lag by 90°

6. A pure capacitor connected across an A.C. voltage consumed 50 W. This is due to________?

   A. the capacitive reactance in ohms
   B. the current flowing in capacitor
   C. the size of the capacitor being quite big
   D. the statement is incorrect

7. In a pure capacitive circuit if the supply frequency is reduced to 1/2, the current will__________?

   A. be reduced by half
   B. be doubled
   C. be four times at high
   D. be reduced to one fourth

8. In a pure inductive circuit if the supply frequency is reduced to 1/2, the current will__________?

   A. be reduced by half
   B. be doubled
   C. be four times as high
   D. be reduced to one fourth

9. A pure inductance connected across 250 V, 50 Hz supply consumes 100 W. This consumption can be attributed to_________?

   A. the big size of the inductor
   B. the reactance of the inductor
   C. the current flowing in the inductor
   D. the statement given is false

10. Pure inductive circuit takes power from the A.C. line when_________?

    A. applied voltage decreases but current increases
    B. applied voltage increases but current decreases
    C. both applied voltage and current increase
    D. both applied voltage and current decrease