The SCR would be turned OFF by voltage reversal of applied anode-cathode ac supply of frequency of | |
A. | 30 kHz [Wrong Answer] |
B. | 15 kHz [Wrong Answer] |
C. | 5 kHz [Correct Answer] |
D. | 20 kHz [Wrong Answer] |
View Answer
Explanation:-
Answer : C Discuss it below : !! OOPS Login [Click here] is required to post your answer/result |
⇒ An n type silicon bar 0.1 cm long and 100 μm^{2} in cross-sectional area has a majority carrier concentration of 5 x 10^{20}/m^{3} and the carrier mobility is 0.13 m^{0}/V-s at 300k. If the charge of an electron is 1.6 x 10^{-19} coulomb, then the resistance of the bar is
10^{6} ohm
10^{4} ohm
10^{-1} ohm
10^{-4} ohm
⇒ 23.6_{10} = __________ _{2}
11111.1001
10111.1001
111.101
10111.1
⇒ A characteristic property of crystal is its periodicity of structure.
TRUE
FALSE
⇒ The probability of recombination of electrons and holes in a semiconductor is proportional to
density of electrons
density of holes
density of electrons and holes
none of the above
⇒ An electron for which l = 0 has zero orbital magnetic dipole moment.
TRUE
FALSE
⇒ An angle modulated signal is given by s(t) = cos 2p (2 x 10^{6}t + 30 sin 150t + 40 cos 150t). The maximum frequency and phase deviations of s(t) are
10.5 kHz, 140p rad
6 kHz and 80p rad
10.5 kHz, 100p rad
7.5 kHz, 100p rad
⇒ A high resistance was measured by loss of charge method. The voltmeter resistance was 10^{10} ohms. The calculation gave the value of unknown resistance as 0.8 x 10^{9} ohms. The true value of resistance is
0.8 x 10^{9} Ω
less than 0.8 x 10^{9} Ω
more than 0.8 x 10^{9} Ω
either (b) or (c)
⇒ A capacitor whose capacitance C_{t} = C_{0} (1- cos ωt) is fed by a sinusoidal voltage v = V_{0} sin ωt. The equation for current i is
ω C_{0}V_{0} cos ωt
ω C_{0}V_{0} sin ωt
ω C_{0}V_{0} (cos ωt - cos^{2} ωt)
none of the above
⇒ Consider the following statements regarding registers and latches:
- Registers are made of edge-triggered FFs, whereas latches are made from level-triggered FFs.
- Registers are temporary storage devices whereas latches are not.
- A latch employs cross-coupled feedback connections.
- A register stores a binary word whereas a latch does not.
1 only
1 and 3
2 and 3
3 and 4
⇒ Limiter is not essential in the following detector
foster-Seeley
ratio detector
balanced
none of the above
⇒ For the block diagram of the given figure, the equation describing system dynamic
(1 + RCs) Δθ_{0}(s) = Δθ_{i}(s) + R Δ H(s)
(1 + RCs) [ΔH(s)] = Δθ(s) - Δθ_{0}(s)
(1 + RCs) Δθ_{0}(s) = RΔ H(s) - Δ θ_{i}(s)
(1 + RCs) Δθ_{i}(s) = Δ H(s)[R] - Δθ_{0}(s)
⇒ The circuit shown in the figure conv
BCD to Binary code
Binary to excess - 3 code
Excess - 3 to Gray
Gray to Binary
⇒ Which of the following is used to obtain output position in a position control system?
Strain gauge
Load cell
Synchro
Thermistor
⇒ Foster Seeley discriminator uses a
single tuned circuit
double tuned circuit with primary and secondary tuned to the same frequency
double tuned circuit with primary and secondary tuned to the different frequency
none of the above
⇒ Consider the following expressions in J
42, 40, 42 respectively
42, 42, 42 respectively
40, 42, 42 respectively
40, 40, 42 respectively
⇒ Which of the following is not correct in C?
6 / 4 = 1
2 / 5 = 0
2.0 / 5 = 0
2.0 / 5.0 = 0.4
⇒
Assertion (A): The modified ramp function of the given figure can be represented s sum of two ramp functions of the given fig
Both A and R are correct and R is correct explanation of A
Both A and R are correct but R is not correct explanation of A
A is true, R is false
A is false, R is true
⇒ Barkhausen criterion is 1 + A_{v}β = 0.
TRUE
FALSE
⇒ All poles and zeros of a driving point immittance function of an L-C network
should lie on the jω axis
should lie on the +ve real axis
should lie on the - ve real axis
can lie anywhere in s-plane
⇒ The power dissipated in 4 Ω resistance in figur
64 W
32 W
16 W
8 W
⇒ In a common Emitter BJT amplifier, the maximum usable supply voltage is limited by
avalanche breakdown of Base emitter junction
collector to Base Breakdown voltage with emitter open (βV_{CBO})
collector Emitter Breakdown voltage with base open (βV_{CBO})
zener breakdown voltage of the emitter base Junction
⇒ A carrier is simultaneously modulated by two sine waves having modulation indices of 0.4 and 0.3. The total modulation index will be
0.1
0.7
0.5
0.35
⇒ 8 bit data can have 256 numbers ranging from 00000000 to 111 111 11.
TRUE
FALSE
⇒ After reflection from a plane conducting surface, the apparent velocity of electromagnetic wave becomes greater than the velocity of light in free space is called
conventional velocity
phase velocity
propagation velocity
group velocity
⇒ Which of the following instructions in 8085 does not belong to data transfer group?L X I rp, data 16
MOV M, r
MVIM, data
ADC M
⇒ A signal x(n) = sin(ω_{0}n + φ) is the input to a linear time invariant system having a frequency response H(e^{jω}) If the O/P of the system is Ax(n -n_{0}), then the general form of H(e^{jω}) will be
- n_{0}ω_{0} + β for any arbitrary real β
- n_{0}ω_{0} + 2pk for any arbitrary integer k
n_{0}ω_{0} + 2pk for any arbitrary integer k
- n_{0}ω_{0} + φ
⇒ In admittance parameter set, the dependent variables are the currents at the two ports.
TRUE
FALSE
⇒
Reason (R): If σ = 0, ke^{st} becomes a sinusoid.
Both A and R are correct and R is correct explanation of A
Both A and R are correct but R is not correct explanation of A
A is true, R is false
A is false, R is true
⇒ Norton's equivalent circuit
is same as Thevenin's circuit
has no relation with Thevenin's circuit
is dual of Thevenin's circuit
is reciprocal of Thevenin's circuit
⇒ In solid dielectrics the rate of deterioration doubles for every 10-12°C rise in temperature.
TRUE
FALSE