Explore topic-wise MCQs in BITSAT.

This section includes 159 Mcqs, each offering curated multiple-choice questions to sharpen your BITSAT knowledge and support exam preparation. Choose a topic below to get started.

101.

Identify the device in the following symbol.

A. Zener diode
B. Varactor diode
C. Tunnel diode
D. Photo diode
Answer» C. Tunnel diode
102.

An ideal rectifier should have transformer utilization factor (TUF) of 1. If the actual TUF is 3.5, it shows that

A. Diode is under-loaded
B. The transformer must be 3.5 times larger
C. The transformer should be only 1/3.5 times the ideal size
D. The ripple factor is low
Answer» C. The transformer should be only 1/3.5 times the ideal size
103.

For the circuit shown in the figure below, assume that D1, D2 and D3 are ideal. v(t) = π sin (100πt) VThe DC components of voltages v1 and v2, respectively are

A. 0 V and 1 V
B. -0.5 V and 0.5 V
C. 1 V and 0.5 V
D. 1 V and 1 V
Answer» C. 1 V and 0.5 V
104.

Each diode of a 3-phase, half-wave diode rectifier conducts for

A. 60°
B. 90°
C. 120°
D. 180°
Answer» D. 180°
105.

Output response of diode clipper circuit shown in the figure will be

A. Both (a) & (b)
B. None of the above
Answer» B. None of the above
106.

In the circuit D1 & D2 are ideal diodes. The current I1 and I2 are

A. 0, 2 mA
B. 2 mA, 0
C. 8 mA, 0
D. 0, 8 mA
Answer» E.
107.

Assume that the diode D1 is ideal and D2 has cut-in voltage of 0.3 V as given in the circuit below. Find out the values of labeled voltage and current.

A. 8 V, 0.5 mA
B. 7.57 V, 0.5 mA
C. 8 V, 0.24 mA
D. 7.57 V, 0.24 mA
Answer» E.
108.

In the Figure (a) and (b) shown below, the transformers are identical are ideal, except that the transformer in Figure (b) is centre-tapped. Assuming ideal diodes, the ratio of the root-mean-square (RMS) voltage across the resistor R in Figure (a) to that in Figure (b) is

A. \(\sqrt 2 :1\)
B. 2 : 1
C. \(2\sqrt 2 :1\)
D. 4 : 1
Answer» C. \(2\sqrt 2 :1\)
109.

In the following circuit, the input voltage \({V_{in}}\) is \(100\;sin\left( {100\pi t} \right)\). For \(100\pi RC = 50\), the average voltages across \(R\) (in volts) under steady-state is nearest to

A. 100
B. 31.8
C. 200
D. 63.6
Answer» D. 63.6
110.

A half-wave rectifier has an input voltage of 240 V rms. If the step-down transformer has a turns ratio of 8 ∶ 1, what is the peak load voltage? Ignore diode drop.

A. 27.5 V
B. 86.5 V
C. 30.0 V
D. 42.5 V
Answer» E.
111.

In a full wave rectifier without filter, the ripple factor is

A. 0.482
B. 1.21
C. 1.79
D. 2.05
Answer» B. 1.21
112.

In a linear IC voltage regulator, series pass transistor always operates in _____ region.

A. Active
B. Saturation
C. Cut-off
D. All of the above
Answer» B. Saturation
113.

If diodes are ideal in the circuit shown in the given figure, then determine the maximum value of Vout during the positive half of the input signal.

A. Vp – 4V
B. Vp – 6V
C. 4V
D. 6V
Answer» D. 6V
114.

In the circuit shown below 18 V Zener diode has zero Zener resistance and a knee current of 2 mA. The minimum value of R so that voltage across it does not fall below 18 V is:

A. 1000 Ω
B. 500 Ω
C. 9000 Ω
D. 2000 Ω
Answer» B. 500 Ω
115.

In case of full wave rectifier the ripple factor is

A. 1.21
B. 0.50
C. 0.48
D. 1.00
Answer» D. 1.00
116.

A tunnel diode is fabricated from:

A. Ge
B. Si
C. GaAs
D. Ge or GaAs
Answer» E.
117.

Consider the circuit shown in the given figure. If the maximum value of input voltage is Vm, then what is the DC level of output voltage V0?

A. Vm
B. -Vm
C. 2Vm
D. -2Vm
Answer» B. -Vm
118.

A voltage regulator is a circuit which

A. Converts the ac voltage to dc voltage
B. Smoothens the ac variation in dc output voltage
C. Maintains a constant dc output voltage inspite of the fluctuations in ac input voltage or load current
D. None of the above
Answer» D. None of the above
119.

In a P-N-P transistor, majority charge carriers are:

A. Holes
B. Electrons
C. Both 1 & 2
D. None of these
Answer» B. Electrons
120.

For thyristors pulse triggering is preferred than dc triggering because:

A. Gate dissipation is low
B. Pulse system is simpler
C. Triggering signal is required for short duration
D. All the above
Answer» E.
121.

A limiter circuit is also known as a:

A. clamp circuit
B. chopping circuit
C. clipper circuit
D. chopper circuit
Answer» D. chopper circuit
122.

Determine the resonant frequency of an IMPATT diode having the following specifications:Carrier drift velocity: 2 × 107 cm/sDrift-region length: 5 μmMaximum operating voltage: 100 VMaximum operating current: 250 mAEfficiency: 20%Breakdown voltage: 90 V

A. 16.67 GHz
B. 15 GHz
C. 20 GHz
D. 25 GHz
Answer» D. 25 GHz
123.

Consider the above circuit, for \({V_i} = {V_m}\sin \omega t\), the output voltage V0 for \({R_1} \to \infty\) will be:

A. Zero
B. Vm
C. 2 Vm
D. -Vm
Answer» D. -Vm
124.

Figure shown below capacitor c is initially charged to V0 = 50 V with upper plate positive. Switch S is closed at t = 0. Current through the circuit at t = 0 and final voltage across C are respectively

A. 15 A, 200 V
B. 25 A, 250 V
C. 20 A, 200 V
D. 15 A, 150 V
Answer» B. 25 A, 250 V
125.

A Silicon diode operating at a temperature of 300 K has a bias current of 2 mA. Find the dynamic resistanceTake: η = 1

A. 13 Ω
B. 26 Ω
C. 1.3 Ω
D. 2.6 Ω
Answer» B. 26 Ω
126.

Identify the given rectifier.

A. Half-wave rectifier
B. Full-wave rectifier
C. Bridge rectifier
D. Centre-tapped rectifier
Answer» B. Full-wave rectifier
127.

For forward biased diode

A. Transition capacitance is larger than diffusion capacitance
B. Diffusion capacitance is larger than transition capacitance
C. Both capacitances are having same value
D. Cannot predict with certainty
Answer» C. Both capacitances are having same value
128.

Match the two lists and choose the correct answer from the code given below:List IList II(a) vrms of half-wave rectifier output(i)\(\frac{(2V_m)}{π}\)(b) Vrms of bridge rectifier output(ii)\(\frac{(V_m)}{π}\)(c) Vdc (half-wave rectifier output)(iii) V(d) Vdc (full-wave rectifier output)(iv)\(\frac{(V)}{\sqrt2}\)

A. (a) – (ii), (b) – (iii), (c) – (iv), (d) – (i)
B. (a) – (iv), (b) – (iii), (c) – (i), (d) – (ii)
C. (a) – (iii), (b) – (iv), (c) – (i), (d) – (ii)
D. (a) – (iv), (b) – (iii), (c) – (ii), (d) – (i)
Answer» E.
129.

If the diodes in the circuit shown are ideal and the breakdown voltage VZ of the Zener diode is 5 V, the power dissipated in the 100 Ω resistor (in watts) is_____

A. 0
B. 1
C. 25/100
D. 225/100
Answer» B. 1
130.

A silicon diode is preferred to a germanium diode because of its

A. Higher reverse current
B. Lower reverse current and higher reverse break down voltage
C. Higher reverse current and lower reverse break down voltage
D. None of the above
Answer» C. Higher reverse current and lower reverse break down voltage
131.

A half-wave rectifier circuit using ideal diode has an input voltage of 20 sin ωt Volt. Then average and rms values of output voltage respectively, are

A. \(\frac{{10}}{\pi }V\;and\;5\;V\)
B. \(\frac{{20}}{\pi }V\;and\;10\;V\)
C. \(\frac{{20}}{\pi }V\;and\;5\;V\)
D. \(\frac{{10}}{\pi }V\;and\;10\;V\)
Answer» C. \(\frac{{20}}{\pi }V\;and\;5\;V\)
132.

A non-ideal diode is biased with a voltage of -0.03 V, and a diode current of I1 is measured. The thermal voltage is 26 mV and the ideality factor for the diode is 15/13. The voltage, in V, at which the measured current increases to 1.5 I1 is closest to:

A. -0.02
B. -0.09
C. -1.50
D. -4.50
Answer» C. -1.50
133.

A clamper circuit1. Adds or subtracts a dc voltage to or from a waveform2. Does not change the shape of the waveformWhich of the above statements is/are correct?

A. 1 only
B. 2 only
C. Both 1 and 2
D. Neither 1 nor 2
Answer» D. Neither 1 nor 2
134.

Identify the given waveform

A. Positive half wave rectifier
B. Full wave rectifier
C. Dual full wave rectifier
D. Negative half wave rectifier
Answer» B. Full wave rectifier
135.

In a full wave rectifier, the current in each diode flows for

A. Half cycle of the input signal
B. Full cycle of the input signal
C. Quarter cycle of input signal
D. Three fourth cycle of input signal
Answer» B. Full cycle of the input signal
136.

A 1-phase diode bridge rectifier connected from 100 V rms ac supply is feeding a resistive, load Neglecting diode drop, the output average voltage is approximately.

A. 90.0 V
B. 63.7 V
C. 141 V
D. 45 V
Answer» B. 63.7 V
137.

For the network given below, what is the value or RL that will turn the Zener diode ON and also what is the maximum wattage rating of the diode?

A. 200 Ohm, 300 mW
B. 250 Ohm, 300 mW
C. 250 Ohm, 320 mW
D. 300 Ohm, 350 mW
Answer» D. 300 Ohm, 350 mW
138.

Consider the diode circuit shown below. The diode, D, obeys the current-voltage characteristic \({I_D} = {I_S}\left( {\exp \left( {\frac{{{V_D}}}{{n{V_T}\;}}} \right) - 1} \right)\), where n > 1, VT > 0, VD is the voltage across the diode and ID is the current through it. The circuit is biased so that voltage, V > 0 and current, I < 0. If you had to design this circuit to transfer maximum power from the current source (I1) to a resistive load (not shown) at the output, what values of R1 and R2 would you choose?

A. Large R1 and large R2
B. Small R1 and small R2
C. Large R1 and small R2
D. Small R1 and large R2
Answer» E.
139.

If the input ( Vin ) to the circuit is a sine wave, the output will be

A. Half - wave rectified sine wave
B. Full - wave rectified sine wave
C. Triangular wave
D. Square wave
Answer» E.
140.

_____ is an electromechanical device that consists of an actuator mechanically linked to a set of contacts. When an object comes into the contact with the actuator, the device operates the contacts to make or break an electrical connection.

A. A relay
B. A photoelectric switch
C. A circuit breaker
D. A limit switch
Answer» E.
141.

Find the values of VO, VD2 and ID for the circuit given below:

A. V0 = 2 VVD2 = 10 VID = 0.5 A
B. V0 = 10 VVD2 = 2 VID = 0 A
C. V0 = 5 VVD2 = 1 VID = 2 A
D. V0 = 0 VVD2 = 12 VID = 0 A
Answer» E.
142.

IC 7812 is a _____ voltage regulator.

A. 78 V
B. 8 V
C. 21 V
D. 12 V
Answer» E.
143.

Consider the following diodes:1. Gunn diode2. Schottky diode3. Crystal diode4. Tunnel diodeWhich of these can be used as detector diodes?

A. 1 and 2 only
B. 2 and 4 only
C. 3 and 4 only
D. 1, 2, 3 and 4
Answer» C. 3 and 4 only
144.

If the output of a voltage regulator varies from 15 to 14.7 V between the minimum and maximum load current, the load regulation is:

A. 0
B. 1%
C. 2%
D. 5%
Answer» D. 5%
145.

In an L-section filter, a bleeder resistance connected across the load

A. provides good regulation for all values of load
B. ensures lower PIV of the diodes
C. ensures lower values of capacitance in the filter
D. reduces ripple content
Answer» B. ensures lower PIV of the diodes
146.

Assuming the diodes to be ideal in the figure, for the output to be clipped, the input voltage Vi must be outside the range

A. -1 V to -2 V
B. -2 V to -4 V
C. +1 V to -2 V
D. +2 V to -4 V
Answer» C. +1 V to -2 V
147.

A 1N755 Zener diode is connected (in reverse biased mode) in series to a 620 Ω resistor and a 20 V DC supply. Calculate the diode current.

A. 20.16 mA
B. 12.16 mA
C. 28.49 mA
D. 30.12 mA
Answer» B. 12.16 mA
148.

______ has the highest mobility.

A. Ions
B. Electrons
C. Neutron
D. Proton
Answer» C. Neutron
149.

Peak factor for a half wave rectified sine wave is

A. 1.41
B. 1.73
C. 1
D. 2
Answer» E.
150.

A zener diode is invariably used with

A. Forward bias
B. Reverse bias
C. Either forward bias or reverse bias
D. Zero bias
Answer» C. Either forward bias or reverse bias