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1.  The only AC waveform that produces a current flow with the same waveform as the voltage is the:

2.  Look at the following diagram: The waveshape shown in the diagram is:

3.  When the positive period of an AC waveshape is not equal to the negative period, the waveform is known as:

4.  A rotating machine producing a voltage with an alternating waveform at its terminals is called:

6.  The following formula can be used to determine the value of the voltage induced in a rotating loop: In the formula the term B stands for the:

7.  Look at the following diagram: The basic construction of an alternator has been shown to be a loop rotating in a magnetic field, as illustrated. This result can also be achieved by:

8.  A conductor 0.25 m long is rotating on the periphery of an armature at 25 ms^{–1}. If the flux density is 0.3 T, then the voltage induced in the conductor when it is cutting the field at an angle of 60º will be approximately:

9.  The iron core onto which the coils of an alternator are wound improves the voltage output by increasing the flux density, but causes two undesirable effects, these are:

10.  In an alternator, hysteresis loss results in energy loss in the form of:

11.  The eddycurrent losses in alternators may be greatly reduced by using cores which are made of:

12.  The hysteresis losses in the core of an alternator can be kept within reasonable limits by using:

13.  Some of the design techniques used in alternators such as, distributed windings, variation of air gaps and the setting of conductors at an angle, are used to:

14.  In Australia, the standard frequency of supply is:

15.  Look at the following drawing: The drawing shows a sinewave of voltage. If the voltage has a frequency of 50 Hz, then the periodic time of the waveshape will be:

16.  The frequency of the output voltage of an alternator can be determined using the following formula: f = n P/120 In the formula the term P stands for the:

17.  In order to generate a voltage at a frequency of 50 Hz, a 6 pole alternator must each be driven at a speed of:

18.  Look at the following diagram: With reference to the sinewave of voltage shown, if the maximum value of the voltage is 340 volts, then the value of the instantaneous voltage at 30 ° will be:

19.  A sinewave of current has a maximum value of 15 amperes. Using the formula I = I_{max} sin θ the instantaneous current at 60° will be approximately:

20.  A sinewave of current has a maximum value of 12 amperes. The average value of current will be approximately:

21.  A sine wave of voltage has a maximum value of 155.6 V. The RMS value of the voltage will be approximately:

22.  For any waveform, the crest factor is defined as the ratio of the:

23.  For any waveform, the form factor is defined as the ratio of the:

24.  For a sinewave, the form factor is:

25.  Look at the following diagram: With reference to the diagram, the current:

26.  When drawing a phasor diagram for a series AC circuit, the:

27.  Look at the following diagram: With reference to the diagram, the current is shown:

28.  Look at the following diagram: In the phasor diagram shown, the:

29.  Two voltages A and B have been connected in series. Voltage A is 100 V and leads the current by 30º, while voltage B is 80 V and lags the current by 25º. Using the trigonometric method, the resultant voltage will be approximately:

30.  A perfect square wave would consist of:

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