MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 1800 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.
| 1351. |
A sinusoidal current having peak value of 7.07 A is superimposed on dc of 5A. If a hot-wire ammeter is used to measure the combined current in the circuit, it will indicate __________ ampere. |
| A. | 7.07 |
| B. | 10 |
| C. | 12.07 |
| D. | 2.07 |
| Answer» B. 10 | |
| 1352. |
If a sheet of a mica is inserted between the plates of an air capacitor, the capacitance |
| A. | will increase |
| B. | will return the same |
| C. | will decrease |
| D. | may increase or decrease |
| Answer» B. will return the same | |
| 1353. |
Two impedances 10 - j 10 and 10 + j 10 are connected in parallel. Their combined impedance is |
| A. | 5 + j5 |
| B. | 5 - j5 |
| C. | 10 + j0 |
| D. | 20 - j10 |
| Answer» D. 20 - j10 | |
| 1354. |
Assertion (A): In KVL equations involving mutually coupled circuits the sign of M terms can be positive or negative.Reason (R): Dot convention helps in determining sign of M terms in KVL equations. |
| A. | Both A and R are true and R is correct explanation of A |
| B. | Both A and R are true and R is not the correct explanation of A |
| C. | A is true but R is false |
| D. | A is false but R is true |
| Answer» D. A is false but R is true | |
| 1355. |
The voltage transfer functions of two port circuits connected in cascade can be easily found from |
| A. | product of individual ABCD matrices |
| B. | product of voltage transfer functions of two networks |
| C. | sum of z matrices |
| D. | sum of h matrices |
| Answer» B. product of voltage transfer functions of two networks | |
| 1356. |
If impedance of a circuit is defined as then circuit is said to be in resonance if |
| A. | ab = cd |
| B. | bc = ad |
| C. | ac = bd |
| D. | none |
| Answer» C. ac = bd | |
| 1357. |
A square current wave of magnitude 1 A is applied to an element for 5 seconds. The voltage across the element rises linearly from 0 to final value linearly. The element is |
| A. | resistance |
| B. | inductance |
| C. | capacitance |
| D. | R and C in series |
| Answer» D. R and C in series | |
| 1358. |
In figure, power in 6 Ω resistor is zero then V = |
| A. | 202∠45° |
| B. | 20 ∠30° |
| C. | 20 ∠45° |
| D. | 202∠30° |
| Answer» B. 20 ‚à†30¬∞ | |
| 1359. |
In most electric irons, the thermister used for controlling temperature is |
| A. | vapour-filled bulb |
| B. | high-expansion steel rod |
| C. | bimetallic strip |
| D. | thermopile |
| Answer» D. thermopile | |
| 1360. |
Which of the following expressions is true for apparent power in an A.C. circuit? |
| A. | VI cos Φ |
| B. | Vav x Iav |
| C. | Vr.m.s x Ir.m.s |
| D. | Vpeak x Ipeak |
| Answer» D. Vpeak x Ipeak | |
| 1361. |
A series RLC circuit is supplied from a variable frequency source. The resonant frequency is ω0. The voltage across L is maximum at a frequency |
| A. | equal to ω0 |
| B. | slightly less than ω0 |
| C. | slightly more than ω0 |
| D. | none of the above |
| Answer» D. none of the above | |
| 1362. |
When R and C are connected in parallel, phase angle of Y is positive. |
| A. | 1 |
| B. | |
| Answer» B. | |
| 1363. |
A 2 mH inductor with some initial current can be represented as shown below, where s is the Laplace transform variable. The value of initial current is |
| A. | 0.5 A |
| B. | 1.0 A |
| C. | 2.0 A |
| D. | 0.0 A |
| Answer» B. 1.0 A | |
| 1364. |
If A = 4∠7°, A2 is |
| A. | 16∠14° |
| B. | 16∠49° |
| C. | 16∠7° |
| D. | 16∠3.5 |
| Answer» B. 16‚à†49¬∞ | |
| 1365. |
In the circuit, the value of the voltage source E is |
| A. | -22 V |
| B. | -12 V |
| C. | +12 V |
| D. | -10 V |
| Answer» B. -12 V | |
| 1366. |
When a lead acid cell discharges, the specific gravity of electrolyte increases. |
| A. | 1 |
| B. | |
| Answer» C. | |
| 1367. |
The design of wave filter is based on characteristic impedance which is |
| A. | pure resistance |
| B. | pure reactance |
| C. | pure resistance in pass band and pure reactance in attenuation band |
| D. | pure reactance in pass band and pure resistance in attenuation band |
| Answer» D. pure reactance in pass band and pure resistance in attenuation band | |
| 1368. |
The distance between the plates of a parallel plate capacitor is d. The dielectric is in two parts, each of equal thickness but dielectric constants ‚àà1 and ‚àà2 respectively. The total capacitance will be proportional to |
| A. | |
| B. | ‚àà1 - ‚àà2 |
| Answer» B. ‚àà1 - ‚àà2 | |
| 1369. |
If Va0, Va1, Va2 are sequence components of Va and Ia0, Ia1, Ia2 are sequence components of Ia, then total 3 phase power P is given by |
| A. | P = Va0Ia0 + Va1Ia1 + Va2Ia2 |
| B. | P = Va0Ia0 + Va1Ia1 + Va2Ia2* |
| C. | P = 3(Va0Ia0 + Va1Ia1 + Va2Ia2) |
| D. | P = 3(Va0Ia0 + Va1Ia1 + Va2Ia2*) |
| Answer» E. | |
| 1370. |
The admittance parameter Y12 in the 2 port network in the figure |
| A. | -0.2 mho |
| B. | 0.1 mho |
| C. | -0.05 mho |
| D. | 0.05 mho |
| Answer» C. -0.05 mho | |
| 1371. |
The r.m.s. value of a half-wave rectified current is 100 A. Its value for full-wave rectification would be __________ amperes. |
| A. | 141.4 |
| B. | 200 |
| C. | 200/p |
| D. | 40/p |
| Answer» B. 200 | |
| 1372. |
In an R-C circuit, there is an initial voltage of 3 V across the capacitor. In s domain equivalent circuit, the voltage source to take into account the initial voltage has a strength of |
| A. | |
| B. | 3s |
| Answer» B. 3s | |
| 1373. |
For an ac circuit having capacitance C, instantaneous current i and instantaneous voltage e are related as |
| A. | 1 |
| B. | |
| Answer» B. | |
| 1374. |
S is closed for a long time and steady state is reached. S is opened at t(0-). The voltage marked V is V0 at t = 0+ and Vf at t = ‚àû. Then value of V0 and Vf are respectively |
| A. | 8, 8 |
| B. | 0, 1 |
| C. | 4, 0 |
| D. | 4, 8 |
| Answer» E. | |
| 1375. |
The correct relation between joules and calories is |
| A. | calories = joules/4.156 |
| B. | joules = calories/4.156 |
| C. | calories = joules x 107/4.156 |
| D. | joules = calories x 107/4.156 |
| Answer» B. joules = calories/4.156 | |
| 1376. |
The following differential equation has |
| A. | degree = 2, order = 1 |
| B. | degree = 3, order = 2 |
| C. | degree = 4, order = 3 |
| D. | degree = 2, order = 3 |
| Answer» C. degree = 4, order = 3 | |
| 1377. |
For a half wave rectified voltage, the form factor and peak factor respectively are |
| A. | 1.11 and 2 |
| B. | 1.57 and 2 |
| C. | 1.11 and 1.11 |
| D. | 1.57 and 2 |
| Answer» C. 1.11 and 1.11 | |
| 1378. |
If , the network has |
| A. | 1 H inductor and 1 F capacitor in parallel |
| B. | 1 H inductor and 1 F capacitor in series |
| C. | 1 H inductor and 1 Ω resistor in series |
| D. | 1 H inductor and 1 Ω resistor in parallel |
| Answer» B. 1 H inductor and 1 F capacitor in series | |
| 1379. |
Permittivity has the units of F/m. |
| A. | 1 |
| B. | |
| Answer» B. | |
| 1380. |
The output voltage of a charger is |
| A. | less than battery voltage |
| B. | same as battery voltage |
| C. | more than battery voltage |
| D. | same or more than battery voltage |
| Answer» D. same or more than battery voltage | |
| 1381. |
If Z(s) is positive real, then where k has only positive real values is also positive real. This hypothesis was first given by |
| A. | O'Brune |
| B. | R. Richards |
| C. | Bott and Duffin |
| D. | P. S. Laplace |
| Answer» C. Bott and Duffin | |
| 1382. |
The scale factor for half wave and full wave rectifier is __________ respectively. |
| A. | 1.11, 1.414 |
| B. | 1.11, 1.57 |
| C. | 1.57, 1.11 |
| D. | 1.414, 1.11 |
| Answer» E. | |
| 1383. |
Three capacitors each 9 μF are connected in delta. The value of each capacitor in equivalent star connection is |
| A. | 3 μF |
| B. | 6 μF |
| C. | 27 μF |
| D. | 81 μF |
| Answer» D. 81 ŒºF | |
| 1384. |
An excitation is applied to a system at t = T, and its response is zero for -‚àû < t < T, such a system is |
| A. | non-causal system |
| B. | Stable system |
| C. | causal system |
| D. | unstable system |
| Answer» D. unstable system | |
| 1385. |
A resistance R, inductance L and capacitance C are in series. The source frequency is adjusted to be equal to resonant frequency. The lower half power frequency is ω1. Another resistance R is added in series with the circuit. The new lower half power frequency will be |
| A. | ω1 |
| B. | less than ω1 |
| C. | more than ω1 |
| D. | either more than ω1 or less then ω1 |
| Answer» D. either more than œâ1 or less then œâ1 | |
| 1386. |
In terms of z parameters, the condition for the network to be passive is |
| A. | z11 = z22 |
| B. | z12 = z21 |
| C. | z11 = 0 |
| D. | z22 = 0 |
| Answer» C. z11 = 0 | |
| 1387. |
One coulomb charge is equal to the charge on |
| A. | 6.24 x 1018 electrons |
| B. | 6.24 x 1024 electrons |
| C. | 6.24 x 1018 atoms |
| D. | none of the above |
| Answer» B. 6.24 x 1024 electrons | |
| 1388. |
Two independence parameters Z11 and Z12 of the two-port network in the figure are |
| A. | Z11 = 2.75 Ω and Z12 = 0.25 Ω |
| B. | Z11 = 3 Ω and Z12 = 0.5 Ω |
| C. | Z11 = 3 Ω and Z12 = 0.25 Ω |
| D. | Z11 = 2.25 Ω and Z12 = 0.5 Ω |
| Answer» B. Z11 = 3 Œ© and Z12 = 0.5 Œ© | |
| 1389. |
The equivalent resistance between terminals x and y figure is |
| A. | 150 Ω |
| B. | 45 Ω |
| C. | 55 Ω |
| D. | 35 Ω |
| Answer» E. | |
| 1390. |
Two RLC series circuit has same damping ratio. Circuit 1 has higher natural frequency as compared to circuit 2. Then |
| A. | transients in circuit 2 will decay faster |
| B. | transients in circuit 1 will decay faster |
| C. | transients in both circuits will decay at the same rate |
| D. | transients in any one may decay faster than in the other |
| Answer» C. transients in both circuits will decay at the same rate | |
| 1391. |
For a reactance function H(s), the slope dH (jω)/dω is |
| A. | 0 |
| B. | always positive |
| C. | always negative |
| D. | either 0 or positive |
| Answer» C. always negative | |
| 1392. |
Transformer coil is an insulator. |
| A. | 1 |
| B. | |
| Answer» B. | |
| 1393. |
In ZRC(s) has a pole at s = 0, the first element in second Foster realization is |
| A. | R |
| B. | C |
| C. | R and C in series |
| D. | R and C in parallel |
| Answer» B. C | |
| 1394. |
The colour coding of a resistors shows 100 K, ± 10%. When the resistance was measured with an ohmmeter, it read |
| A. | 95 K |
| B. | 80 K |
| C. | 120 K |
| D. | 85 K |
| Answer» B. 80 K | |
| 1395. |
The strength of controlled voltage source depends on |
| A. | value of current elsewhere in the circuit |
| B. | value of voltage elsewhere in the circuit |
| C. | value of current or voltage elsewhere in the circuit |
| D. | none of the above |
| Answer» D. none of the above | |
| 1396. |
Choose the correct option Transit period is the time between two steady stateTransient Response is the response due to internal energy stored in circuitTransit response is also called natural responseTransit response arises due to presence of C and L in the circuitTransit is due to R, L, C in the circuit |
| A. | 4, 3, 2 , 1 |
| B. | 5, 4, 3, 2 |
| C. | 5, 4, 3, 1 |
| D. | 5, 1, 4 |
| Answer» B. 5, 4, 3, 2 | |
| 1397. |
Permeability is analogous to |
| A. | conductivity |
| B. | resistivity |
| C. | retentivity |
| D. | coercivity |
| Answer» B. resistivity | |
| 1398. |
The phase velocity v in a transmission line is |
| A. | LC |
| B. | C/L |
| C. | L/C |
| D. | 1/LC |
| Answer» E. | |
| 1399. |
Figure shows a pole zero plot of I(s). The likely current response in time domain is |
| A. | i (t) = e-1 - e-3t |
| B. | i (t) = e-1 - 2e-2t |
| C. | i (t) = e-1 - e-2t |
| D. | i (t) = e-1 - e-4t |
| Answer» C. i (t) = e-1 - e-2t | |
| 1400. |
KCL is a statement of principle of conservation of energy. |
| A. | 1 |
| B. | |
| Answer» C. | |