chapter 4 ME327
True
. For operation in the linear or active region, the base-emitter junction of a transistor is forwardbiased.
(b) decrease
. If the amplitude of Vin in Figure 4-22 is decreased, the ac output voltage amplitude will
(a) increase
. If the base resistor in Figure 4-38 is open, the transistor collector voltage will
(a) increase
. If the emitter in Figure 4-38 becomes disconnected from ground, the collector voltage will
(d) base, emitter, collector
1. The three terminals of a bipolar junction transistor are called
a) increase
1. if a transistor with a higher bDC is used in Figure 4-9, the collector current will
(c) an internal ac resistance
10. When a lowercase is used in relation to a transistor, it refers to
False
11. Amplification is the output voltage divided by the input current.
True
12. A transistor in cutoff acts as an open switch.
(b) switch
12. When operated in cutoff and saturation, the transistor acts like a
(f) c and d - maximum and equal to VCC
13. In cutoff, VCE is
(c) minimum
14. In saturation, VCE is
(b) directly proportional to light intensity
17. In a phototransistor, base current is
(d) both (b) an LED and a photodiode (c) an LED and a phototransistor
19. An optocoupler usually consists of
(a) increase
2. If a transistor with a higher bDC is used in Figure 4-9, the emitter current will
(a) positive with respect to the emitter
3. For operation as an amplifier, the base of an npn transistor must be
True
8. When a transistor is saturated, the collector current is maximum.
(b) decrease
9. If the transistor in Figure 4-38 is open from collector to emitter, the voltage across RC will
False
9. bDC and hFE are two different transistor parameters.
(c) OL
A DMM measuring on open transistor junction shows
True
A bipolar junction transistor has three terminals
False
Cutoff and saturation are the two normal states of a linear transistor amplifier.
(c) 50
If IC is 50 times larger than IB, then bDC is
c) not change
If VCC in Figure 4-16 is increased, the base current will
(c) not change
If a transistor with a higher bDC is used in Figure 4-9, the base current will
(c) 50
If the output of a transistor amplifier is 5 V rms and the input is 100 mV rms, the voltage gain is
c) not change
If the transistor in Figure 4-24 is saturated and the base current is increased, the collector current will
(a) increase
If the transistor in Figure 4-38 is open from collector to emitter, the collector voltage will
(b) 110
In a given transistor amplifier, and the voltage gain is
(c) emitter and collector
In a pnp transistor, the p regions are
(a) VCC
In a transistor amplifier, if the base-emitter junction is open, the collector voltage is
(b) will not affect the collector current
Once in saturation, a further increase in base current will
(a) increase
RC in Figure 4-24 is reduced in value, the value of IC(sat) will
(b) 0.7 V
The approximate voltage across the forward-biased base-emitter junction of a silicon BJT is
(a) current gain
The bDC of a transistor is its
(a) forward-reverse
The bias condition for a transistor to be used as a linear amplifier is called
(a) greater than the base current (c) greater than the collector current / (d) a and c
The emitter current is always
(a) IC bDCIl
The relationship between the collector current and a light-generated base current is
False
The three regions of a BJT are base, emitter, and cathode
(b) IB IC(sat)/bDC
To saturate a BJT,
True
Two types of BJT are npn and pnp
True
Voltage gain of a transistor amplifier depends on the collector resistor and the internal ac resistance
False
base current and collector current are approximately equal.
(b) decrease
if VBB is reduced in Figure 4-16, the collector current will
False
the dc voltage gain of a transistor is designated as bDC
