MCQ
2541. In the normal operation of an SCR, anode is-- with respect to cathode.
at zero potential
negative
positive
none of the above
2542. Which causes the barrier layer in a PN Junction--
doping
barrier potential
recombination
ions
2543. The most commonly used semiconductor is-
germanium
carbon
sulphur
silicon
2544. As the temperature of a transistor goes up the base-emitter resistance-
decreases
increases
remains the same
none
2545. In an LC oscillator, the frequency of oscillation is:
Proportional to LC
Proportional to square root of LC
Inversely proportional to the square root of LC
Independent of the value of LC
2546. A zener diode is destroyed if it-
is forward biased
is reverse biased
carriers more than rated current
none of the above
2547. The battery connections required to forword bias a pn junction are-
+ve terminal to p and -ve terminal to n
-ve terminal to pand+ ve terminal to n
-ve terminal to p and-ve terminal to n
+ve terminal to pand+ ve terminal to n
2548. Transistor biasing represents --conditions.
ac
both ac & dc
dc
none
2549. If a power supply has no-load and full-load voltages of 30V and 25V respectively, then the percentage voltage regulation is:
10%
20%
15%
25%
2550. The output frequency of a full wave rectifier is-
Same as the input frequency
One-half of the input frequency
Double of the input frequency
Independent of the input frequency
2551. The purpose of a gate is to---
deliver molten metal into the mold cavity.
act as a reservoir for the molten metal.
feed the molten metal to the casting in order to compensate for the shrinkage.
deliver molten metal from pouring basin to gate
2552. A voltage divider consists of two 100k resistors and a 12V source. What will the output voltage be if a load resistor of 1 MQ is connected to the output?
0.57V
12V
5.7 V
6 V
2553. A PN junction acts as a--
unidirectional switch
bidirectional switch
controlled switch
none of the above
2554. The point of intersection of de and ac load lines is called-
saturation
operating
cut off
none of these
2555. The reverse current in a diode is of the order of—
KA
A
mA
uA
2556. Noise factor of a ideal amplifier is---
0dB
5dB
0.5dB
10dB
2557. An SCR has PN junctions.
Two
Four
Three
None of the above
2558. 1 db corresponds to --- changes in voltage level.
12%
20%
80%
26%
2559. RC coupling is used for---amplification.
voltage
power
current
none
2560. For highest power gain, one would use-- configuration.
CE
CB
CC
none of these