Questions and answers for exam Preparation

MCQs

Total Questions : 67 | Page 6 of 7 pages

Question 51. Let U and V be two independent zero mean Gaussian random variables of variances 1/4 and 1/9 respectively. The probability P(3V â‰¥ 2U ) is

Discuss Question

Answer: Option B. -> 1/2

-NA-

Question 52. The impulse response of a continuous time system is given by h(t) = Î´(t - 1) + Î´(t - 3). The value of the step response at t = 2 is

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Answer: Option B. -> 1

-NA-

Question 53. Two magnetically uncoupled inductive coils have Q factors q1 and q2 at the chosen operating frequency. Their respective resistances are R1 and R2. When connected in series, their effective Q factor at the same operating frequency is

q1 + q2
(1/q1) + (1/q2)
(q1R1 + q2R2)/(R1 + R2)
(q1R2 + q2R1)/(R1 + R2)

Discuss Question

Answer: Option C. -> (q1R1 + q2R2)/(R1 + R2)

-NA-

Question 54. An infinitely long uniform solid wire of radius a carries a uniform dc current of density j.
The magnetic field at a distance r from the center of the wire is proportional to

r for r < a and 1/r2 for r > a
0 for r < a and 1/r for r > a
r for r < a and 1/r for r > a
0 for r < a and 1/r2 for r > a

Discuss Question

Answer: Option C. -> r for r < a and 1/r for r > a

-NA-

Question 55. A hole of radius b (b The magnetic field inside the hole is

uniform and depends only on d
uniform and depends only on b
uniform and depends on both b and d
non uniform

Discuss Question

Answer: Option A. -> uniform and depends only on d

-NA-

Question 56. A and B are friends. They decide to meet between 1 PM and 2 PM on a given day. There is a condition that whoever arrives first will not wait for the other for more than 15 minutes. The probability that they will meet on that day is

1/4
1/16
7/16
9/16

Discuss Question

Answer: Option C. -> 7/16

-NA-

Question 57. There are eight bags of rice looking alike, seven of which have equal weight and one is slightly
heavier. The weighing balance is of unlimited capacity. Using this balance, the minimum number
of weighings required to identify the heavier bag is

Discuss Question

Answer: Option A. -> 2

-NA-

Question 58. The maximum value of f(x) = x3 - 9x2 +24x + 5 in the interval [1, 6] is

Discuss Question

Answer: Option C. -> 41

-NA-

Question 59. 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