MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 902 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.
| 451. |
The dirac delta function δ(t) is defined as |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» E. | |
| 452. |
A voltage wave is v = 50 sin ωt. Its average value calculated over full one cycle is |
| A. | zero |
| B. | 35.36 V |
| C. | 31.85 V |
| D. | none of the above |
| Answer» B. 35.36 V | |
| 453. |
The current in a circuit with 10 Ω resistance is i = 3 + 4 sin (100 t + 45°) + 4 sin (300 t + 60°) A. The rms current and power dissipated are |
| A. | √41 A and 410 W |
| B. | √35 A and 350 W |
| C. | 5 A and 250 W |
| D. | 11 A and 1210 W |
| Answer» D. 11 A and 1210 W | |
| 454. |
In the given figure 15.6 shows a series, R - C circuit fed by a current source i(t). There is an initial voltage v₀ across the capacitor. The system |
| A. | is linear |
| B. | is non linear |
| C. | may be linear or non linear |
| D. | is linear only if v₀ is zero |
| Answer» E. | |
| 455. |
A signal m(t) with bandwidth 500 Hz is first multiplied by a signal g(t) where g(t) ids given by below equation. The resulting signal is then passed through on ideal low pass filter with bandwidth 1 kHz. The output of the low pass filter would me |
| A. | δ(t) |
| B. | m(t) |
| C. | 0 |
| D. | m(t) δ(t) |
| Answer» C. 0 | |
| 456. |
Assertion (A): Fourier series can also be written in exponential form.Reason (R): sin (n ωt) and cos (n ωt) can be expressed as sum or difference of exponentials. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is true, R is false |
| D. | A is false, R is true |
| Answer» B. Both A and R are correct but R is not correct explanation of A | |
| 457. |
A linear system is characterized by H(ω) = Be^(-2ω²) the system is physically |
| A. | unrealizable |
| B. | realizable |
| C. | depends upon B |
| D. | depends upon constant 2 |
| Answer» B. realizable | |
| 458. |
Assertion (A): Intergal of a unit step function is a ramp of slope unity.Reason (R): If f(t) = sin wt, F(s) = 1/(s² + w²) |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is true, R is false |
| D. | A is false, R is true |
| Answer» D. A is false, R is true | |
| 459. |
The function δ' (t-b) is |
| A. | a step function originating at t = b |
| B. | an impulse function originating at t = b |
| C. | a unit doublet originating at = t - b |
| D. | none of the above |
| Answer» D. none of the above | |
| 460. |
The minimum sampling frequency in sample/sec. required to reconstruct the following signal from its samples without distortion would be |
| A. | 2 x 10³ |
| B. | 4 x 10³ |
| C. | 6 x 10³ |
| D. | 8 x 10³ |
| Answer» D. 8 x 10³ | |
| 461. |
In the given figure the phase angle of Fn is either 0 or Π. |
| A. | True |
| B. | False |
| C. | May be True or False |
| D. | Can't Say |
| Answer» B. False | |
| 462. |
Consider the following two statements : |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is true, R is false |
| D. | A is false, R is true |
| Answer» B. Both A and R are correct but R is not correct explanation of A | |
| 463. |
A rectangular pulse train s(t) is shown in figure is convolved with the signal cos²(4π x 10³t). The convolved signal will be a |
| A. | DC |
| B. | 12 kHZ sinusoidal |
| C. | 8 kHZ sinusoidal |
| D. | 14 kHZ sinusoidal |
| Answer» E. | |
| 464. |
Consider the following statements : |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is true, R is false |
| D. | A is false, R is true |
| Answer» B. Both A and R are correct but R is not correct explanation of A | |
| 465. |
For the function u(t - a) = 0 for t < a and u(t - a) = 1 fort ≥ a, the Laplace transform is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» C. C | |
| 466. |
The value of following Integral is equal to |
| A. | 11 |
| B. | 3 |
| C. | 9 |
| D. | 0 |
| Answer» E. | |
| 467. |
Let the Fourier transform of y(n) be given by below equation, then y(e^(j0)) is |
| A. | 1/4 |
| B. | 2 |
| C. | 4 |
| D. | 4/3 |
| Answer» B. 2 | |
| 468. |
Consider the following equation. |
| A. | True |
| B. | False |
| C. | May Be True or False |
| D. | Can't Say |
| Answer» B. False | |
| 469. |
Inverse Laplace transform of 2s+5 / (s²+5s+6) is |
| A. | 2 exp (- 2.5 t) cosh (0.5 t) |
| B. | exp (- 2 t) + exp (- 3 t) |
| C. | 2 exp (- 2.5 t) sinh (0.5 t) |
| D. | 2 exp (- 2.5 t) cos 0.5 t |
| Answer» C. 2 exp (- 2.5 t) sinh (0.5 t) | |
| 470. |
If x(z) is the Z transform of sequence xk, the z transform of sequence (kxk)is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» C. C | |
| 471. |
The eigen values of the following matrix are |
| A. | 1, 1 |
| B. | - 1, - 1 |
| C. | j, - j |
| D. | 1, - 1 |
| Answer» E. | |
| 472. |
If f(t)↔ F(jω), and f(t) is real, then F(- jω) |
| A. | F(jω) |
| B. | F*(j↔) |
| C. | F*(- jω) |
| D. | none of these |
| Answer» C. F*(- jω) | |
| 473. |
The z-transform of sequence n x x[n] is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» B. B | |
| 474. |
If x^k = 2^k for k ≤ 0 and xk = 0 for k ≥ 0, Z transform of the sequence x is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» E. | |
| 475. |
If H(z) is given by following equation, the poles of H(z) are at |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» B. B | |
| 476. |
Consider below given statements: |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is true, R is false |
| D. | A is false, R is true |
| Answer» C. A is true, R is false | |
| 477. |
If H(f) = y(t)/x(t), then for this to be true x(t) is |
| A. | exp (j2π f/t) |
| B. | exp (-j2π f/t) |
| C. | exp (j2π ft) |
| D. | exp (-j2π f/t) |
| Answer» D. exp (-j2π f/t) | |
| 478. |
The analog signal m(t) is given below m(t) = 4 cos 100 πt + 8 sin 200 πt + cos 300 πt, the Nyquist sampling rate will be |
| A. | 1/100 |
| B. | 1/200 |
| C. | 1/300 |
| D. | 1/600 |
| Answer» D. 1/600 | |
| 479. |
Consider z transform of a signal as given below, then the response will be |
| A. | IIR |
| B. | FIR |
| C. | Depends on value of n |
| D. | Cannot determined |
| Answer» C. Depends on value of n | |
| 480. |
For the differential equation (D³ - D² + D -1) [y(t)] = 0, the root of auxiliary equation are |
| A. | -j, j, 1 |
| B. | -j, j, 2 |
| C. | 1, 2, j |
| D. | 1, 2, -j |
| Answer» B. -j, j, 2 | |
| 481. |
Fourier transform of unit step function is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» E. | |
| 482. |
Which is the Laplace transform of x(t) = -e^(2t) ∪(t) ⊕ t ∪(t)? |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» C. C | |
| 483. |
If X(z) = 2az¯¹/(1 - az¯¹)³ and |a| < |z|, then the initial value x₀ is |
| A. | 0 |
| B. | 1 |
| C. | ∞ |
| D. | 2 |
| Answer» B. 1 | |
| 484. |
Assertion (A): L[e^(-at) f(t)] = F(s + a) Reason (R): In use of Laplace transform method, initial conditions may be neglected. |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is true, R is false |
| D. | A is false, R is true |
| Answer» C. A is true, R is false | |
| 485. |
The Laplace transform of unit ramp function starting at t = a is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» D. D | |
| 486. |
Which one of following is a static system? |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» E. | |
| 487. |
The joint probability function of two discrete random variable X and Y is given by following equation. Then E(X) = |
| A. | 8/14 |
| B. | 40/14 |
| C. | 16/14 |
| D. | 12/14 |
| Answer» C. 16/14 | |
| 488. |
The function f(t) in the given figure will have its Laplace transform as |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» E. | |
| 489. |
The period of the following function is |
| A. | s/8 |
| B. | 8s |
| C. | 4s |
| D. | s/4 |
| Answer» C. 4s | |
| 490. |
Let x(t) and y(t) with F.T. x(f) and y(f) respectively be related as shown in figure. Then y(f) is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» C. C | |
| 491. |
The z-transform of a particular signal is given below. The system after implementation will be |
| A. | casual and stable |
| B. | non-casual and stable |
| C. | non-casual and unstable |
| D. | casual and unstable |
| Answer» B. non-casual and stable | |
| 492. |
Assertion (A): The modified ramp function of the given figure can be represented s sum of two ramp functions of the given figure.Reason (R): If f(t) = t, F(s) = 1 |
| A. | Both A and R are correct and R is correct explanation of A |
| B. | Both A and R are correct but R is not correct explanation of A |
| C. | A is true, R is false |
| D. | A is false, R is true |
| Answer» D. A is false, R is true | |
| 493. |
If Laplace transform of f(t) is F(s), then £ f(t - a) u (t - a)= 0 |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» C. C | |
| 494. |
The sampling of a function f(l) = sin 2πf₀t starts from a zero crossing. The signal can be detected if sampling time T is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» D. D | |
| 495. |
If F(s) = 2s+3 / (s+1)(s+2), the terms in f(t) will have |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» B. B | |
| 496. |
If F(s) is given by following equation, the coefficient of term e^(-t) in f(t) will be |
| A. | 1 |
| B. | 0 |
| C. | 0.5 |
| D. | 2/3 |
| Answer» E. | |
| 497. |
The final value theorem is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» B. B | |
| 498. |
Laplace transform of a pulse function of magnitude E and duration from t = 0 to t = a is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» D. D | |
| 499. |
If £[f(t)] = F(s), then £[f(t - T)] = |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» C. C | |
| 500. |
If A and B are given by below diagram, then A + B is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» B. B | |