Q.1
Piezoelectric quartz crystal resonators find application where
  • Signal amplification is required
  • Rectification of the signal is required
  • Signal frequency control is required
  • Modulation of signal is required
Q.2
Which of the following could be the maximum current rating of junction diode by 126?
  • 1 A
  • 10 A
  • 20 A
  • 100 A
Q.3
The sensitivity of human eyes is maximum at
  • White portion of spectrum
  • Green portion of spectrum
  • Red portion of spectrum
  • Violet portion of spectrum
Q.4
The amount of photoelectric emission current depends on
  • Frequency of incident radiation
  • Intensity of incident radiation
  • Both frequency and intensity of incident radiation
  • None of the above
Q.5
The output, V-I characteristics of an Enhancement type MOSFET has
  • Only an ohmic region
  • Only a saturation region
  • An ohmic region at low voltage value followed by a saturation region at higher voltages
  • An ohmic region at large voltage values preceded by a saturation region at lower voltages
Q.6
In a bipolar transistor, the base collector junction has
  • Forward bias
  • Reverse bias
  • Zero bias
  • Zero or forward bias
Q.7
Assertion (A): A p-n junction has high resistance in reverse direction.Reason (R): When a reverse bias is applied to p-n junction, the width of depletion layer increases.
  • Both A and R are true and R is correct explanation of A
  • Both A and R are true but R is not a correct explanation of A
  • A is true but R is false
  • A is false but R is true
Q.8
A transistor has a current gain of 0.in the CB mode. Its current gain in the CC mode is
  • 100
  • 99
  • 1.01
  • 0.99
Q.9
Which of the following has highest resistivity?
  • Mica
  • Paraffin wax
  • Air
  • Mineral oil
Q.10
At room temperature the current in an intrinsic semiconductor is due to
  • Holes
  • Electrons
  • Ions
  • Holes and electrons
Q.11
If too large current passes through the diode
  • All electrons will leave
  • All holes will freeze
  • Excessive heat may damage the diode
  • Diode will emit light
Q.12
An intrinsic silicon sample has 1 million free electrons at room temperature. As the temperature is increased
  • The number of free electrons increases
  • The number of free electrons increases but the number of holes decreases
  • The number of free electrons and holes increase by the same amount
  • The number of free electrons and holes increase but not by the same amount
Q.13
The depletion layer width of Junction
  • Decreases with light doping
  • Is independent of applied voltage
  • Is increased under reverse bias
  • Increases with heavy doping
Q.14
In a half wave rectifier, the load current flows
  • Only for the positive half cycle of the input signal
  • Only for the negative half cycle of the input signal
  • For full cycle
  • For less than fourth cycle
Q.15
Assertion (A): In p-n-p transistor collector current is termed negative.Reason (R): In p-n-p transistor holes are majority carriers.
  • Both A and R are true and R is correct explanation of A
  • Both A and R are true but R is not a correct explanation of A
  • A is true but R is false
  • A is false but R is true
Q.16
How many free electrons does a p type semiconductor has?
  • Only those produced by thermal energy
  • Only those produced by doping
  • Those produced by doping as well as thermal energy
  • Any of the above
Q.17
Light dependent resistors are
  • Highly doped semiconductor
  • Intrinsic semiconductor
  • Lightly doped semiconductor
  • Either A or B
Q.18
In a bipolar transistor, the emitter base junction has
  • Forward bias
  • Reverse bias
  • Zero bias
  • Zero or reverse bias
Q.19
Free electrons exist in
  • First band
  • Second band
  • Third band
  • Conduction band
Q.20
When avalanche breakdown occurs covalent bonds are not affected.
  • True
  • False
0 h : 0 m : 1 s