MCQOPTIONS
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MCQOPTIONS
This section includes 1085 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics & Communication Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 151. |
A short dipole antenna is__________. |
| A. | Left end-fed |
| B. | Right end-fed |
| C. | Centre-fed |
| D. | None of these |
| Answer» D. None of these | |
| 152. |
The direction of electric field due to +0 positive charge is |
| A. | Away from the charge |
| B. | Towards the charge |
| C. | Both (a) & (b) |
| D. | None of the above |
| Answer» B. Towards the charge | |
| 153. |
Below the cut-off frequency, there is_______________. |
| A. | Attenuation |
| B. | No attenuation |
| C. | Amplification |
| D. | None of these. |
| Answer» B. No attenuation | |
| 154. |
Wave guides are a type of _________ filter. |
| A. | Low pass |
| B. | All pass |
| C. | Band pass |
| D. | High pass |
| Answer» E. | |
| 155. |
The Smith chart represents a family of circles obtained by varyingnormalized resistance in the range of __________. |
| A. | −1 to 0 |
| B. | 0 to 1 |
| C. | 0 to ∞ |
| D. | −∞ to ∞ |
| Answer» D. −∞ to ∞ | |
| 156. |
For lossless wave guides, σc ________and σ ______ |
| A. | ∞, 0 |
| B. | 0, ∞ |
| C. | 0, 0 |
| D. | ∞, ∞ |
| Answer» B. 0, ∞ | |
| 157. |
Electrostatic field is _________ a perfect conductor. |
| A. | same inside |
| B. | infinite inside |
| C. | zero inside |
| D. | none of these |
| Answer» D. none of these | |
| 158. |
Another boundary condition using Maxwell's equations is given as__________. |
| A. | Htan '1' + Htan '2' = 0 |
| B. | Htan '1' − Htan '2' = 0 |
| C. | Htan '1' + Htan '2' = Js |
| D. | Htan '1'− Htan '2' = Js |
| Answer» E. | |
| 159. |
The vector product obeys the __________ law. |
| A. | Commutative |
| B. | Associative |
| C. | Distributive |
| D. | Parallelogram |
| Answer» D. Parallelogram | |
| 160. |
In a Spherical coordinate system, φ is given as _________. |
| A. | y/x |
| B. | x/y |
| C. | tan−1(y/x) |
| D. | tan−1(x/y) |
| Answer» D. tan−1(x/y) | |
| 161. |
Curl measures _________. |
| A. | rate of change of vector |
| B. | circular rotation |
| C. | both (a) and (b) |
| D. | none of these |
| Answer» D. none of these | |
| 162. |
If antenna directivity and antenna gain are equal, then antennaefficiency is __________%. |
| A. | 20 |
| B. | 50 |
| C. | 75 |
| D. | 100 |
| Answer» E. | |
| 163. |
Electric intensity at any point in an electric field is equal to the at thatpoint. |
| A. | electric flux |
| B. | magnetic flux density |
| C. | potential gradient |
| D. | none of the above |
| Answer» D. none of the above | |
| 164. |
Antenna array is__________. |
| A. | 1-D |
| B. | 2-D |
| C. | Either (a) or (b) |
| D. | None of these |
| Answer» D. None of these | |
| 165. |
As per Gauss' Law, charge density inside a perfect conductor is zeroif E is _________. |
| A. | positive |
| B. | negative |
| C. | unity |
| D. | zero |
| Answer» E. | |
| 166. |
The value of dielectric constant for vacuum is taken as |
| A. | zero |
| B. | 1 |
| C. | 4 |
| D. | 10 |
| Answer» C. 4 | |
| 167. |
Loss tangent is the same as _________. |
| A. | mutual inductance |
| B. | resistivity |
| C. | conductivity |
| D. | dissipation factor |
| Answer» E. | |
| 168. |
Which of the following is/are vector quantity(s)? |
| A. | force |
| B. | electric field intensity |
| C. | acceleration |
| D. | all of these |
| Answer» E. | |
| 169. |
Surface current density K on wave guide walls for ______ is given as |
| A. | TM mode |
| B. | TE mode |
| C. | Both (a) and (b) |
| D. | None of these |
| Answer» D. None of these | |
| 170. |
In the case of a perfect dielectric medium, phase constant______________ as conductivity increases. |
| A. | Increases |
| B. | Decreases |
| C. | Remains unchanged |
| D. | None of these |
| Answer» B. Decreases | |
| 171. |
If work done Wmn is zero, then VN and VM are related as _______. |
| A. | VN + VM = 0 |
| B. | VN − VM = 0 |
| C. | 2VN + VM = 0 |
| D. | VN + 2VM = 0 |
| Answer» C. 2VN + VM = 0 | |
| 172. |
Cylindrical coordinate 'r' is related to the Cartesian coordinate as__________. |
| A. | (x, y) |
| B. | (x + y) |
| C. | (x2/y2) |
| D. | (x2 + y2)1/2 |
| Answer» E. | |
| 173. |
If a 6 (iF capacitor is charged to 200 V, the charge in coulombs will be |
| A. | 800 uC |
| B. | 900 uC |
| C. | 1200 uC |
| D. | 1600 uC |
| Answer» D. 1600 uC | |
| 174. |
In a _________ transmission line, the reflection coefficient domain isa circle of unitary radius. |
| A. | Lossy |
| B. | Lossless |
| C. | None of these |
| D. | Cannot say |
| Answer» C. None of these | |
| 175. |
In low-power applications, ideal SWR is___________. |
| A. | 1:1 |
| B. | 1:2 |
| C. | 2:1 |
| D. | 2:2 |
| Answer» B. 1:2 | |
| 176. |
There will be force of attraction between two current-carrying conductors if the currents are in __________ direction. |
| A. | Same |
| B. | Opposite |
| C. | None of these |
| D. | Cannot say |
| Answer» B. Opposite | |
| 177. |
A transmission line is specified in terms of _________. |
| A. | R, G,L |
| B. | G, L,C |
| C. | R, G, L,C |
| D. | None of these |
| Answer» D. None of these | |
| 178. |
In a distortionless line, attenuation constant α is frequency_________. |
| A. | Dependent |
| B. | Independent |
| C. | None of these |
| D. | Cannot say |
| Answer» C. None of these | |
| 179. |
On the basis of magnetic behaviour, materials are classified into _________ categories. |
| A. | 2 |
| B. | 3 |
| C. | 4 |
| D. | 5 |
| Answer» E. | |
| 180. |
Which of the following capacitor has relatively shorter shelf life? |
| A. | Mica capacitor |
| B. | Electrolytic capacitor |
| C. | Ceramic capacitor |
| D. | Paper capacitor |
| Answer» C. Ceramic capacitor | |
| 181. |
A unit vector has its magnitude as ____________. |
| A. | 0 |
| B. | 1 |
| C. | ∞ |
| D. | none of these |
| Answer» C. ∞ | |
| 182. |
The value of E within the field due to a point charge can be found withthe help of |
| A. | Faraday's laws |
| B. | Kirchhoff s laws |
| C. | Coulomb's laws |
| D. | none of the above |
| Answer» D. none of the above | |
| 183. |
Impedance of an antenna is matched to feed___________. |
| A. | Line |
| B. | Radio |
| C. | Both (a) and (b) |
| D. | None of these |
| Answer» D. None of these | |
| 184. |
The sparking between two electrical contacts can be reduced byinserting a |
| A. | Capacitor in parallel with contacts |
| B. | Capacitor in series with each contact |
| C. | Resistance in line |
| D. | None of the above |
| Answer» B. Capacitor in series with each contact | |
| 185. |
In planar transmission lines, C = _________. |
| A. | σ b/d |
| B. | μ d/b |
| C. | b/d |
| D. | None of these. |
| Answer» D. None of these. | |
| 186. |
Capacitors are used for audio frequency and radio frequency couplingand tuning. |
| A. | Air |
| B. | Mica |
| C. | Plastic film |
| D. | Ceramic |
| Answer» C. Plastic film | |
| 187. |
Total flux passing through a closed surface held in a magnetic field is__________. |
| A. | Infinity |
| B. | Zero |
| C. | Unity |
| D. | None of these |
| Answer» C. Unity | |
| 188. |
The cross product of the same vector to itself is ____________. |
| A. | 0 |
| B. | 1 |
| C. | ∞ |
| D. | 100 |
| Answer» B. 1 | |
| 189. |
ε0 is ________ F/m. |
| A. | 8.854 × 10−12 |
| B. | 6.654 × 10−12 |
| C. | 8.854 × 10−10 |
| D. | 6.654 × 10−10 |
| Answer» B. 6.654 × 10−12 | |
| 190. |
Magnetic field at any point inside a long solenoid is _________. |
| A. | zero |
| B. | infinity |
| C. | constant |
| D. | none of these |
| Answer» D. none of these | |
| 191. |
The dissipation factor of good dielectric is of the order of |
| A. | 0.0002 |
| B. | 0.002 |
| C. | 0.02 |
| D. | 0.2 |
| Answer» B. 0.002 | |
| 192. |
Loss tangent approximates _________. |
| A. | attenuation constant |
| B. | phase constant |
| C. | intrinsic impedance |
| D. | all of these |
| Answer» E. | |
| 193. |
"The surface integral of the normal component of the electric displacement D over any closed surface equals the charge enclosed by the surface". The above statement is associated with |
| A. | Gauss's law |
| B. | Kirchhoff s law |
| C. | Faraday's law |
| D. | Lenz's law |
| Answer» B. Kirchhoff s law | |
| 194. |
Laplacian operator ________. |
| A. | is a scalar function |
| B. | is a vector function |
| C. | can be a scalar or vector function |
| D. | none of these |
| Answer» D. none of these | |
| 195. |
Electric displacement is a quantity. |
| A. | scalar |
| B. | vector |
| C. | both of the above |
| D. | none of the above |
| Answer» C. both of the above | |
| 196. |
The electric field at a point situated as a distance d from straightcharged conductor is |
| A. | Proportional to d |
| B. | Inversely proportional to d |
| C. | Inversely proportional to distance |
| D. | None of the above |
| Answer» C. Inversely proportional to distance | |
| 197. |
A field line and equipotential surface are |
| A. | Always parallel |
| B. | Always at 90 angle |
| C. | Inclined at any angle |
| D. | None of the above |
| Answer» B. Always at 90 angle | |
| 198. |
According to Faraday's __________ Law, as long as changes happenin magnetic flux, induced emf persists. |
| A. | First |
| B. | Second |
| C. | Third |
| D. | Fourth |
| Answer» B. Second | |
| 199. |
As per Stoke's Theorem, = _________. |
| A. | ∞ |
| B. | 1 |
| C. | None of these |
| Answer» D. | |
| 200. |
Multiplication of two vectors is __________. |
| A. | vector |
| B. | scalar |
| C. | either vector or scalar |
| D. | cannot say |
| Answer» D. cannot say | |