IkodeAutomation

Q23. Which of the following factors concerning the sinusoidal alternating quantities is useful in the applications like insulation testing and measurement of iron losses?
a)Q-factor
b) utilization factor
c) peak factor
d) form factor

ANS: option C

Q24. For a symmetrical alternating waveform,the average value over a complete cycle is always _____?
a) 0
b) 0.637
c) 0.707
d) 1.414

ANS: a

Q25. In the case of an alternating current or voltage with a symmetrical waveform, the average value is always found by considering a period of_____.
a) whole cycle
b) half cycle
c) quarter cycle
d) none of the above

ANS :b

Q26. In a purely capacitive circuit , if the supply frequency is doubled ,the current will be____.
a) doubled
b) reduced to half
c) four times as high
d) reduced to one fourth

ANS: a

Q27. The r.m.s. value of a sinusoidal alternating current is equal to its instantaneous value at a phase angle (in degree) of_____.
a)90°
b) 60°
c) 45°
d) 30°

ANS: C

Q28. For a sinusoidal alternating quantity , the value of form factor is_____.
a)1.414
b) 1.11
c) 0.707
d) 0.637

ANS: b

Q29. The form factor of the d.c. supply voltage is_____.
a) infinite
b) 1.0
c) 0.5
d) 0

ANS: b

Q30. For a full-wave rectified sinusoidal alternating current with a peak value Im,the r.m.s. value is____.
a)0.707Im
b)0.637Im
c)0.318Im
d) zero

ANS: a

Q. For a square wave, the form factor is_____.
a) 1.3
b) 1.2
c) 1.1
d) 1.0

ANS: option d.

Q. A transistor can be protected from needless overheating by____.
a) a current-limiting resistor.
b) bleeder resistors.
c)maximizing the drive.
d) shorting out the power supply when the circuit is off.

ANS: option C

Q14. A bleeder resistor ______.
a)is connected across the Capacitor in a power supply.
b) keeps a transistor from drawing too much currents.
c) prevents an amplifier from being over driven.
d) optimizes the efficiency of an amplifier.

ANS: option b

Q15. A phasor is_____.
a) a line representing the magnitude of an alternating quantity.
b) a line which represents the magnitude and direction of an alternating quantity.
c) a line which represent the magnitude and phase of an alternating quantity.
d) none of the above.

ANS: option C.

Q18. If the supply frequency of the purely inductive circuit is reduced to half, the current in the circuit will be______.
a) four times as high
b) halved
c) doubled
d) remains the same

ANS: option C