Image
1.0.0
MCQ
2541. Which causes the barrier layer in a PN Junction--
doping
barrier potential
recombination
ions
2542. 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
2543. RC coupling is used for---amplification.
voltage
power
current
none
2544. A zener diode is destroyed if it-
is forward biased
is reverse biased
carriers more than rated current
none of the above
2545. Transistor biasing represents --conditions.
ac
both ac & dc
dc
none
2546. 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%
2547. When transistor is used as an amplifier, it is operated in the:
Cut off region
Saturation region
Active region
Both a and b
2548. The point of intersection of de and ac load lines is called-
saturation
operating
cut off
none of these
2549. Noise factor of a ideal amplifier is---
0dB
5dB
0.5dB
10dB
ব্যাখ্যা: There is no noise in a ideal amplifier. So, noise factor is 0 dB
2550. The most commonly used semiconductor is-
germanium
carbon
sulphur
silicon
2551. The reverse current in a diode is of the order of—
KA
A
mA
uA
2552. As the temperature of a transistor goes up the base-emitter resistance-
decreases
increases
remains the same
none
ব্যাখ্যা: As temperature increase, the thermal runway properly of transistor becomes more prominent and base-emitter resistance will decreases.
2553. 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
2554. 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
2555. The maximum efficiency of a half-wave diode rectifier is --
50%
25%
40.0%
81.2%
2556. In the normal operation of an SCR, anode is-- with respect to cathode.
at zero potential
negative
positive
none of the above
2557. For highest power gain, one would use-- configuration.
CE
CB
CC
none of these
ব্যাখ্যা: For highest power gain, CE configuration is used. In CE configuration, biasing capacitor is used to balance the operating point to obtain highest power gain
2558. 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
2559. A PN junction acts as a--
unidirectional switch
bidirectional switch
controlled switch
none of the above
ব্যাখ্যা: The PN junction is conduct with forward bias only. It means they conduct in only one direction (Current flows from P to N) That's why PN Junction acts as unidirectional twitch
2560. 1 db corresponds to --- changes in voltage level.
12%
20%
80%
26%