ECE Questions
GATE-2013
Q: The bit rate of a digital communication system is R kbits s/ . The modulation used
is 32-QAM. The minimum bandwidth required for ISI free transmission is
- A: R/10 Hz
- B: R/10 kHz
- C: R/5 Hz
- D: R/5 kHz
GATE-2013
Q: Let U and V be two independent zero mean Gaussain random variables of
variances 1/4 and 1/9 respectively. The probability P(3V ≥ 2U) F is
- A: 4/9
- B: 1/2
- C: 2/3
- D: 5/9
GATE-2019
Q: Radiation resistance of a small dipole current element of length l at a frequency of 3 GHz is 3 ohms. If
the length is changed by 1%, then the percentage change in the radiation resistance, rounded off two
decimal places, is __________%.
GATE-2019
Q: If X and Y are random variables such that E[2X+Y] = 0 and E[X+2Y] = 33, the E[X]+E[Y] =
GATE-2013
Q: A bulb in a staircase has two switches, one switch being at the ground floor
and the other one at the first floor. The bulb can be turned ON and also can
be turned OFF by any one of the switches irrespective of the state of the
other switch. The logic of switching of the bulb resembles
- A: AND
- B: OR
- C: XOR
- D: NAND
GATE-2015
Q: Suppose x[n] is an absolutely summable discrete-time signal. Its z-transform is a rational
function with two poles and two zeroes. The poles are at z = ± 2j. Which one of the
following statements is TRUE for the signal x[n]?
- A: It is a finite duration signal.
- B: It is a causal signal.
- C: It is a non-causal signal.
- D: It is a periodic signal
GATE-2016
Q: In an 8085 system, a PUSH operation requires more clock cycles than a POP operation. Which
one of the following options is the correct reason for this?
- A: For POP, the data transceivers remain in the same direction as for instruction fetch
(memory to processor), whereas for PUSH their direction has to be reversed.
- B: Memory write operations are slower than memory read operations in an 8085 based
system.
- C: The stack pointer needs to be pre-decremented before writing registers in a
PUSH, whereas a POP operation uses the address already in the stack pointer.
- D: Order of registers has to be interchanged for a PUSH operation, whereas POP uses their
natural order.
GATE-2016
Q: The open-loop transfer function of a unity-feedback control system is given by
G(s)=k/s(s+2).For the peak overshoot of the closed-loop system to a unit step input to be
10%, the value of K is __________.
- A: 2.86
- B: 3.86
- C: 1.36
- D: 7.86
GATE-2017
Q: A three dimensional region R of finite volume is described by x2 + y2 ≤ z3; 0≤z≤1,
Where x, y, z are real. The volume of R (up to two decimal places) is ___________.
Q: Collector current is approximately zero in
- A: Cutoff region
- B: Linear region
- C: Saturation region
- D: Breakdown region
Q: αdc value ranges from
- A: 0.90 to 1.99
- B: 0.05 to 0.99
- C: 0.95 to 0.99
- D: 0.00 to 1.00
Q: Pn junction joining base region and emitter region is called
- A: Base-emitter junction
- B: Base-collector junction
- C: Emitter-collector junction
- D: Emitter-body junction
Q: An amplifier is a circuit that can give a power gain
- A: Less than 1
- B: Zero
- C: Greater than 1
- D: Infinite