The output power of the cascaded amplifier / attenuator system can be determined using___________?

Related Mcqs:

1. Harmonics in 3 phase inverters can be reduced by using___________?

   A. Passive filter
   B. Active filter
   C. Both passive and active filters
   D. None of these

2. The ac output voltage waveform of VSI and AC output current waveform of CSI respectively is composed of___________?

   A. High dv / dt, low di / dt
   B. Low dv / dt, low di / dt
   C. Low dv / dt, high di / dt
   D. High dv / dt, high di / dt

3. Electrical power output in a d.c. generator is equal to____________?

   A. Electrical power developed in armature – copper losses
   B. Mechanical power input – iron and friction losses
   C. Electrical power developed in armature – iron and copper losses
   D. Mechanical power input – iron and friction losses – copper losses

4. For power output higher than 15 kW, the suitable rectifier is________________?

   A. Single phase
   B. 3 phase
   C. Poly phase
   D. Only (b) and (c)

5. Electrical power output in a D.C. generator is equal to_____________?

   A. Electrical power developed in armature – copper losses
   B. Mechanical power input – iron and friction losses
   C. Electrical power developed in armature – iron and copper losses
   D. Mechanical power input – iron and friction losses – copper losses

6. Power electronics essentially deals with control of a.c. power at____________?

   A. Frequencies above 20 kHz
   B. Frequencies above 1000 kHz
   C. Frequencies less than 10 Hz
   D. 50 Hz frequency

7. A step up chopper has input voltage 110 V and output voltage 150 V. The value of duty cycle is_____?

   A. 0.32
   B. 0.67
   C. 0.45
   D. 0.27

8. In bipolar modulation, the carrier is symmetric about zero with amplitude equal to Cm, the PWM output

   A. Zero
   B. Switches between – 1 / 2 and + 1 / 2
   C. Switches between – 1 and + 1
   D. Switches between 0 and + 1

9. In a 3 phase half wave rectifier, when firing angle is less than 90 degree, then the average dc output voltage becomes__________________?

   A. Positive
   B. Negative
   C. Zero
   D. None of these

10. In a full bridge VSI, in order to avoid the short circuit across the DC bus and the undefined AC output voltage condition, the modulating technique should ensure that___________?

    A. Top switch of each leg is on at any instant
    B. Bottom switch of each leg is on at any instant
    C. Either A. or B.
    D. None of these