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1. As the temperature increases the mobility of electrons __________ .
Options
A. decreases because the number of carries increases with increased collisions
B. increases because the number of carries decreases with decreased collisions
C. remains same
D. none of the above

2. In the circuit below, delay of the EXOR and AND

Logic gates are 20 ?s and 10 ?s respectively, then the wave y^' and y (with initial condition y = 1) will be :
Options
A.
B.
C.
D.

4. The amplitude of a pair of composite sinusoidal signal y(n) = x₁(n) + x₂(n) with x₁(n) = sin (5pn) x₂(n) = 3 sin (5pn) is __________ .
Options
A. 2
B. 3
C. 4
D. 1

5. A TV picture is to be transmitted over a channel of 6 MHz bandwidth at a 35 dB S/N ratio. The capacity of the channel is
Options
A. 50 Mbps
B. 100 Mbps
C. 36 Mbps
D. 72 Mbps

6. If the system T.F. is The differential equation representing the system is
Options
A.
B.
C.
D. none of these

7. What are the values of E_max and E_min displayed on the oscilloscope, when a 1 kV P-P carries is modulated to 50%?
Options
A. 2 kV, 0.5 kV
B. 1 kV, 0.5 kV
C. 0.75 kV, 0.25 kV
D. 0.5 kV, 1.5 kV

8. A n-channel JFET has I_DSS = 2 mA, Gate to source voltage V_GS = - 2 V and trans-conductance is 0.5 mW then pinch-off voltage is __________ .
Options
A. - 2 V
B. 2 V
C. - 4 V
D. 4 V

9. Suppose that the modulating signal is m(t) = 2cos (2pf_mt) and the carrier signal is x_C(t) = A_C cos(2pf_ct), which one of the following is a conventional AM signal without over modulation?
Options
A. x(t) = A_cm(t)cos(2pf_ct)
B. x(t) = A_c [1 + m(t)]cos (2pf_ct)
C.
D. x(t) = A_ccos(2pf_mt)cos(2pf_ct) + A_csin(2pf_mt)sin(2pf_ct)

10. A MOSFET has a threshold voltage of 1 V and oxide thickness of 500 x 10^-8 [?_r = 3.9; ?₀ = 8.85 x 10^-14 F/cm, q = 1.6 x 10^-19 c]. The region under the gate is ion implanted for threshold voltage tailoring. The base and type of impant required to shift threshold voltage to - 1 V are __________ .
Options
A. 8.6 x 10¹¹/cm², p-type
B. 8.6 x 10¹¹/cm², n-type
C. 0.86 x 10⁹/cm², p-type
D. 1.02 x 10¹²/cm², n-type

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