MCQOPTIONS
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MCQOPTIONS
This section includes 869 Mcqs, each offering curated multiple-choice questions to sharpen your BITSAT knowledge and support exam preparation. Choose a topic below to get started.
| 251. |
For BJT, under saturation condition |
| A. | IC = βIB |
| B. | IC > bIB |
| C. | IC is independent of all other parameters |
| D. | IC < βIB |
| Answer» C. IC is independent of all other parameters | |
| 252. |
Thermosetting polymers are |
| A. | injection moulded |
| B. | extruded |
| C. | cast moulded |
| D. | none of the above |
| Answer» D. none of the above | |
| 253. |
If 100 V is the peak voltage across the secondary of the transformer in a half-wave rectifier (without any filter circuit), then the maximum voltage on the reverse-biased diode is |
| A. | 200 V |
| B. | 141.4 V |
| C. | 100 V |
| D. | 86 V |
| Answer» C. 100 V | |
| 254. |
Peak inverse voltage will be highest for |
| A. | half wave rectifier |
| B. | full wave rectifier |
| C. | bridge rectifier |
| D. | three phase full wave rectifier |
| Answer» C. bridge rectifier | |
| 255. |
In an n-p-n transistor biased for operation in forward active region |
| A. | emitter is positive with respect to base |
| B. | collector is positive with respect to base |
| C. | base is positive with respect to emitter and collector is positive with respect to base |
| D. | none of the above |
| Answer» D. none of the above | |
| 256. |
Photoelectric emitters in photo tubes are generally made of |
| A. | alkali metals |
| B. | metals |
| C. | semiconductors |
| D. | metal and semiconductors |
| Answer» B. metals | |
| 257. |
Assertion (A): In intrinsic semiconductors, the charge concentration increases with temperature.Reason (R): At higher temperatures, the forbidden energy gap in semiconductors is lower. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true but R is not a correct explanation of A |
| C. | A is true but R is false |
| D. | A is false but R is true |
| Answer» B. Both A and R are true but R is not a correct explanation of A | |
| 258. |
The effect of a finite gain of operational amplifier used in an integrator is that |
| A. | it would not integrator |
| B. | slope of the O/P will varied with time |
| C. | final value of the O/P |
| D. | there will be instability in the cirucuit |
| Answer» C. final value of the O/P | |
| 259. |
Zener breakdown occurs |
| A. | due to rapture of covalent band |
| B. | mostly in germanium junctions |
| C. | in lightly doped junctions |
| D. | due to thermally generated minority carriers |
| Answer» B. mostly in germanium junctions | |
| 260. |
Dielectric loss due to polarisation occurs in |
| A. | bipolar dielectrics |
| B. | non-metallic dielectrics |
| C. | liquid dielectrics |
| D. | all of the above |
| Answer» B. non-metallic dielectrics | |
| 261. |
In ferromagnetic materials |
| A. | the atomic magnetic moments are antiparallel and unequal |
| B. | the atomic magnetic moments are parallel |
| C. | the constituent is iron only |
| D. | one of the constituents is iron |
| Answer» C. the constituent is iron only | |
| 262. |
In an n type semiconductor the fermi level is 0.35 eV below the conduction band, the concentration of donor atoms is increased to three times. The new position of Fermi level will be |
| A. | 0.35 eV below conduction band |
| B. | about 0.32 eV below conduction band |
| C. | about 0.32 eV above conduction band |
| D. | about 0.1 eV below conduction band |
| Answer» C. about 0.32 eV above conduction band | |
| 263. |
A semiconductor diode is biased in forward direction and carrying current I. The current due to holes in p material is |
| A. | I |
| B. | 0 |
| C. | less than I |
| D. | 0.5 |
| Answer» D. 0.5 | |
| 264. |
Which of these has 3 layers? |
| A. | PIN diode |
| B. | Zener diode |
| C. | Schottky diode |
| D. | Photo diode |
| Answer» B. Zener diode | |
| 265. |
For an insulating material, dielectric strength and dielectric loss should be respectively |
| A. | high and high |
| B. | low and high |
| C. | high and low |
| D. | low and low |
| Answer» D. low and low | |
| 266. |
Transition capacitance is associated with __________ and depletion capacitance is associated with __________ diodes. |
| A. | reverse bias and forward bias |
| B. | forward bias and reverse bias |
| C. | reverse bias and reverse bias |
| D. | forward bias and forward bias |
| Answer» D. forward bias and forward bias | |
| 267. |
Ferromagnetic materials exhibit |
| A. | a linear B-H behaviour |
| B. | a non-linear B-H behaviour |
| C. | an exponential B-H behaviour |
| D. | none of the above |
| Answer» C. an exponential B-H behaviour | |
| 268. |
If the atomic number of germanium is 32, the number of electrons in the outer most shell will be |
| A. | 2 |
| B. | 3 |
| C. | 4 |
| D. | 6 |
| Answer» D. 6 | |
| 269. |
Which of the following devices has substrate? |
| A. | JFET |
| B. | Depletion Type MOSFET |
| C. | Enhancement type MOSFET |
| D. | Both (b) and (c) |
| Answer» E. | |
| 270. |
When reverse bias is applied to a junction diode |
| A. | minority carrier current is increased |
| B. | majority carrier current is increased |
| C. | potential barrier is lowered |
| D. | potential barrier is raised |
| Answer» E. | |
| 271. |
Assertion (A): The capacitance of a reverse biased pin diode is lower than that of reverse biased p-n diode.Reason (R): A PIN diode has an intrinsic layer between p and n regions. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true but R is not a correct explanation of A |
| C. | A is true but R is false |
| D. | A is false but R is true |
| Answer» B. Both A and R are true but R is not a correct explanation of A | |
| 272. |
Assertion (A): The conductivity of an n type semiconductor increases with increase in temperature and increase in density of donor atoms.Reason (R): Diffusion of carriers occurs in semiconductors. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true but R is not a correct explanation of A |
| C. | A is true but R is false |
| D. | A is false but R is true |
| Answer» C. A is true but R is false | |
| 273. |
The SCR would be turned OFF by voltage reversal of applied anode-cathode ac supply of frequency of |
| A. | 30 kHz |
| B. | 15 kHz |
| C. | 5 kHz |
| D. | 20 kHz |
| Answer» D. 20 kHz | |
| 274. |
The channel of JFET consists of |
| A. | p type material only |
| B. | n type material only |
| C. | conducting material |
| D. | either p or n type material |
| Answer» E. | |
| 275. |
In which material do conduction and valence bands overlap |
| A. | insulators |
| B. | conductors |
| C. | both conductor and semiconductor |
| D. | semiconductors |
| Answer» C. both conductor and semiconductor | |
| 276. |
In a bipolar transistor which current is largest |
| A. | collector current |
| B. | base current |
| C. | emitter current |
| D. | base current or emitter current |
| Answer» D. base current or emitter current | |
| 277. |
A JFET behaves as a constant current source when |
| A. | VGS = 0 |
| B. | VGS is less than pinch off voltage |
| C. | VGS = VDS |
| D. | VGS is more than pinch off voltage |
| Answer» E. | |
| 278. |
The output v-i characteristics of enhancement type MOSFET has |
| A. | only an ohmic region |
| B. | only a saturation region |
| C. | an ohmic region at low voltage value and a saturation region at high voltage |
| D. | a saturation region at low voltage value and an ohmic region at high voltage |
| Answer» D. a saturation region at low voltage value and an ohmic region at high voltage | |
| 279. |
A P-N junction diode dynamic conductance is directly proportional to |
| A. | the applied voltage |
| B. | the temperature |
| C. | its current |
| D. | thermal voltage |
| Answer» D. thermal voltage | |
| 280. |
For the n-type semiconductor with n = NP and P = ni² / ND , the hole concentration will fall below the intrinsic value because some of the holes |
| A. | drop back to acceptor impurity states. |
| B. | drop to donor impurity states |
| C. | virtually leave the crystal |
| D. | recombine with the electrons. |
| Answer» E. | |
| 281. |
Assertion (A): A BJT can be used as a switch.Reason (R): In forward active mode emitter base junction is forward biased and base collector junction is reverse biased. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true but R is not a correct explanation of A |
| C. | A is true but R is false |
| D. | A is false but R is true |
| Answer» C. A is true but R is false | |
| 282. |
When a semi-conductor is doped, its electrical conductivity |
| A. | increases |
| B. | decreases in the direct ratio of the doped material |
| C. | decreases in the inverse ratio of the doped material |
| D. | remains unaltered |
| Answer» B. decreases in the direct ratio of the doped material | |
| 283. |
Which of the following material is preferred for transformer cores operating in micro wave frequency range? |
| A. | Ferrites |
| B. | Silicon steel |
| C. | Superalloy |
| D. | Copper |
| Answer» B. Silicon steel | |
| 284. |
A JFET operates in ohmic region when |
| A. | VGS = 0 |
| B. | VGS is less than pinch off voltage |
| C. | VGS = is Positive |
| D. | VGS = VDS |
| Answer» C. VGS = is Positive | |
| 285. |
The main reason why Ni-Zn ferrites are used for audio and T.V. transformers is that |
| A. | they have large saturation magnetization |
| B. | they are easy to fabricate by rolling |
| C. | they are totally free from pores and voids |
| D. | they have a high electrical resistivity |
| Answer» B. they are easy to fabricate by rolling | |
| 286. |
In a triode |
| A. | grid is nearer to cathode than anode |
| B. | grid is nearer to anode than cathode |
| C. | grid is equidistant from anode and cathode |
| D. | any of the above |
| Answer» B. grid is nearer to anode than cathode | |
| 287. |
The I/P impedance (Zi) and the O/P impedance (Zo) of an ideal trans conductance (Voltage controlled current source) amplifier are |
| A. | Zi = 0, Zo = 0 |
| B. | Zi = 0, Zo = ∞ |
| C. | Zi = ∞, Zo = 0 |
| D. | Zi = ∞, Zo = ∞ |
| Answer» E. | |
| 288. |
In an n channel MOSFET, the substrate is connected |
| A. | to negative terminal of battery |
| B. | to positive terminal of battery |
| C. | to either positive or negative terminal of battery |
| D. | none of the above |
| Answer» B. to positive terminal of battery | |
| 289. |
Which of the following is used as a passive component in electronic circuits? |
| A. | Tunnel diode |
| B. | Capacitor |
| C. | Transistor |
| D. | Vacuum tube |
| Answer» C. Transistor | |
| 290. |
What is the function of silicon dioxide layer in MOSFETS? |
| A. | To provide high input resistance |
| B. | To increase current carriers |
| C. | To provide high output resistance |
| D. | Both (a) and (c) |
| Answer» B. To increase current carriers | |
| 291. |
Secondary emission occurs in |
| A. | diode |
| B. | triode |
| C. | tetrode |
| D. | pentode |
| Answer» D. pentode | |
| 292. |
When a voltage is applied to a semiconductor crystal then the free electrons will flow. |
| A. | towards positive terminal |
| B. | towards negative terminal |
| C. | either towards positive terminal or negative terminal |
| D. | towards positive terminal for 1 μs and towards negative terminal for next 1 μs |
| Answer» B. towards negative terminal | |
| 293. |
Assertion (A): The resistivity of intrinsic semiconductor decreases with increase in temperature.Reason (R): The forbidden gap decreases with increase in temperature. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true but R is not a correct explanation of A |
| C. | A is true but R is false |
| D. | A is false but R is true |
| Answer» B. Both A and R are true but R is not a correct explanation of A | |
| 294. |
In a N-type semi-conductor, the concentration of minority carriers is mainly depends on |
| A. | the number of acceptor atoms |
| B. | the number of donor atoms |
| C. | the extent of doping |
| D. | the temperature of the material |
| Answer» E. | |
| 295. |
In a full wave rectifier, the current in each of the diodes flows for |
| A. | the complete cycle of the input signal |
| B. | half cycle of the input signal |
| C. | less than half cycle of the input signal |
| D. | one-fourth cycle of the input signal |
| Answer» C. less than half cycle of the input signal | |
| 296. |
The factor n in the equation for calculating current for a silicon diode is |
| A. | 1 |
| B. | 2 |
| C. | 2.5 |
| D. | 2 for low levels of current and 1 for high levels of current |
| Answer» E. | |
| 297. |
Almost all resistors are made in a monolithic integrated circuit |
| A. | during the entire diffusion |
| B. | while growing the epitaxial layer |
| C. | during the base diffusion |
| D. | during the collector diffusion |
| Answer» B. while growing the epitaxial layer | |
| 298. |
In P-N junction, the region containing the uncompensated acceptor and donor ions is called |
| A. | transition zone |
| B. | depletion region |
| C. | neutral region |
| D. | active region |
| Answer» C. neutral region | |
| 299. |
The emitter follower is widely used in electronic instrument because |
| A. | its voltage gain is less than unity |
| B. | its voltage gain is very high |
| C. | its O/P Impedance is low and input impedance is high |
| D. | its O/P Impedance is high and I/P impedance is low |
| Answer» D. its O/P Impedance is high and I/P impedance is low | |
| 300. |
When atoms are held together by the sharing of valence electrons |
| A. | each atom becomes free to move |
| B. | neutrons start shifting |
| C. | they form a covalent bond |
| D. | some of the electrons are lost |
| Answer» D. some of the electrons are lost | |