All India Institute of Medical Sciences 2007 B.Com Computer Science Auto cad University - Question Paper

25. The 1st and the last critical frequencies (singularities) of a driving point impedance
function of a passive network having 2 types of elements, are a pole and a zero
respectively. The above property will be satisfied by
(A) RL network only
(B) RC network only
(C) LC network only
(D) RC as well as RL networks
26. In the figure shown below, presume that all the capacitors are initially uncharged. If
v,(t)=lOu(t) Volts,v0(t) is provided by
(A) Se °°° Volts
(B) 8(1 — e °°°) Volts
(C) 8u(t) Volts
(D) eight Volts
27. Consider 2 transfer functions
G1(S)=s2+as+b and G2(S)=s2+as+b•
Vo(t)
The 3-dB bandwidths of their frequency responses are, respectively
(A) %Ja2 _4b,%Ja2 +4b
(B) %Ja2 + 4b, %Ja2 — 4b
28. A negative resistance Rneg is connected to a passive network N having driving point
impedance Z1 (s)as shown beneath. For Z2 (s)to be positive real,
Z2(s)
(A) R I
(B) R I —
(C) R 1< ImZ1(ja),va neg —
(D) R
29. In the circuit shown below, the switch was connected to position one at t < 0 and at t = 0, it
is changed to position 2. presume that the diode has zero voltage drop and a storage time t5.
For 0 < t < t5,v is provided by (all in Volts)
(A) v=—5
(B) v=--5
(D) —5 <0
30. The majority carriers in an n-type semiconductor have an avg. drift velocity v in a
direction perpendicular to a uniform magnetic field B. the electric field E induced due to Hall
effect acts in the direction
(A) v x B
(B) Bxv
(C) along v
(D) opposite to v
31. A heavily doped n—type semiconductor has the subsequent data:
Hole-electron mobility ratio : 0.4
Doping concentration : 4.2x 108 atoms/m3
Intrinsic concentration : 1.5x 10 atoms/m3
The ratio of conductance of the n —type semiconductor to that of the intrinsic semiconductor
of identical material and at the identical temperature is provided by
(A) 0.00005
(B) 2,000
(C) 10,000
(D) 20,000
32. For the circuit shown below; presume that the zener diode is ideal with a breakdown
voltage of six Volts. The waveform observed across R is:

Earning:   Approval pending.