Electronics and Communication Engineering - Exam Questions Papers

41. 

Time domain equivalent circuit of the figure is

A.
B.
C.
D. None of the above

Answer: Option A

Explanation:

In the left hand loop (- i1) enters the dot end while for the right handed loop i2 enters the dot end.

This will make both the M terms at first of + ve sign but as i1 = - ve hence ultimately the M term of right hand loop involving i1 = - ve.

V1 = - L1 + M

V2 = L2 - M .


42. 

Locus of a point Z satisfying the equation arg is:

A. Straight line with equation y = x - 3
B. Circle with equation x2 + y2 - 3x + 3y = 0
C. Hyperbola with equation x2 - y2 - 3x - 3y - 2yx = 0
D. None of these

Answer: Option B

Explanation:

Solving this further we will get x2 + y2 - 3x + 3y = 0 which is the equation of circle.


43. 

A silicon PN junction with no bias have a doping concentration of
Nd = 2 x 1016 cm-3 and Na = 1016 cm-3. The space charge width is:

A. 3.345 x 10-3 cm
B. 3.345 x 10-4 cm
C. 3.345 x 10-5 cm
D. 3.345 x 10-6 cm

Answer: Option C

Explanation:

w = 3.345 x 10-5 cm.


44. 

In 8085, Whenever a signal is received at TRAP terminal its program execution is transferred to a subroutine on address __________ .

A. 0000 H
B. 0024 H
C. 002 CH
D. provided by the address generation logic

Answer: Option B

Explanation:

TRAP is considered to be of the highest priority and the address of the subroutine is given by 0024 H.


45. 

If (225)Y = (165)8 find value of Y

A. 7
B. 8
C. 9
D. 11

Answer: Option A

Explanation:

(225)y => 2Y2 + 2Y + 5 = (165)8 => (117)10

2Y2 + 2Y + 5 = 117

Y2 + Y - 56 = 0

Y = 7 or Y = - 8

Y should be 7.