Electronics and Communication Engineering - Networks Analysis and Synthesis

26.
A material for permanent magnet should have
High retentivity
High permeability
Low hysteresis loss
High hysteresis loss
Answer: Option
Explanation:

Only high retentivity will ensure permanent magnetism.


27.
Which of the following frequencies has the greatest period?
20 Hz
200 Hz
20 kHz
200 kHz
Answer: Option
Explanation:
No answer description is available. Let's discuss.

28.
A variable resistance R and capacitive reactance XC are fed by an voltage. The current locus is
a semi circle in 4th quadrant
a semi circle in first quadrant
a straight line in 4th quadrant
a straight line first quadrant
Answer: Option
Explanation:
No answer description is available. Let's discuss.

29.
Two wires A and B have the same cross-section area and are made of the same material. RA = 600 Ω and RB = 100 Ω. The number of times A is longer than B is
6
2
4
5
Answer: Option
Explanation:

RA = 600 Ω, RB = 100 Ω, .


30.
A dc machine has 6 poles all connected in series. Each pole has 9 H inductance and field current is 2 A. Total inductance and total energy stored are
9 H and 18 J
18 H and 36 J
54 H and 108 J
108 H and 216 J
Answer: Option
Explanation:

Total L = 6 x 9 = 54 H.

Energy = x 54 x 22 = 108 J.