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Q1. | The thermionic emission current is given by |

A. | Fermi-Dirac distribution [Wrong Answer] |

B. | Maxwell's equation [Wrong Answer] |

C. | Richardson Dushman equation [Correct Answer] |

D. | Langmuir Child law [Wrong Answer] |

View Answer
Explanation:-
Answer : CDiscuss it below :!! OOPS Login [Click here] is required to post your answer/resultHelp other students, write article, leave your comments |

**Also Read Similar Questions Below :**

⇒ Which of the following microphones has lowest output impedance?

Moving coil

Ribbon

Crystal

Condenser

⇒ In an SCR, the anode current is controlled by

gate current only

external circuit only

both gate current and external circuit

none of the above

⇒ Why does a FM radio station perform better than and AM station radiating the same actual power?

FM is immune to noise

AM has only two sidebands while FM has more

FM uses larger bandwidth for large modulation depth.

Capture effects appears in FM.

⇒ Find the value of K and velocity constant K

*so that the maximum overshoot in the unit step response is 0.2 and the peak time is 1*

_{v}12.37, 0.175

12.86, 2.175

11.36, 1.175

1.86, 0.175

⇒ For the network shown below, the Thevenin voltage and R

_{TH}is equal to _______

0 V, 58.82 Ω

0 V, 96.774 Ω

0 V, 3 KΩ

None of these

⇒ In an AM system, doubling of modulation index doubles the antenna current. The system is

single side band full carrier

vestigial side band

single side band suppressed carrier

double side band full carrier

⇒ Which memory is available in all technologies?

PROM

EEPROM

ROM

EPROM

⇒

**Assertion (A):** If minimum phase system has a gain margin of 8 *dB* and phase margin of 21°, the system is stable.

**Reason (R):** For a minimum phase system both GM and PM must be positive for the system to be stable.

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 correct but R is wrong

R is correct but A is wrong

⇒ In a series ac circuit a voltage of 20 V at 25 Hz causes a current of 0.20 A, while the same voltage at 75 Hz causes a current of 0.12 A. The circuit consists of

R and C in parallel

R and C in series

R and L in series

either (a) or (b)

⇒ Which of the following microphones has highest output impedance?

Carbon

Ribbon

Crystal

Condenser

⇒ A mod-2 counter followed by a mod 5 is same as

mod-7 counter

A decade counter

mod-3 counter

none

⇒ An arrangement of several individual antennas to spaced and phased that their individual contributions combine in one preferred direction and cancel in all other directions, to get greater directive gain or directivity, is known as

directional radiation of antennas

antenna gain stability

array of antennas

none of the above

⇒ If the numerator of Z(

*s*) is one degree higher than denominator, Z(

*s*) has a pole at infinity.

TRUE

FALSE

⇒ In a lag network the input frequency is 100

*f*where

_{c}*f*is critical frequency. The voltage gain is

_{c}0 dB

-20 dB

-40 dB

-60 dB

⇒ The enhancement type MOSFET is called a

normally on MOSFET

normally off MOSFET

P-type MOSFET

N-type MOSFET

⇒ In figure I

_{D}= 4 mA. Then V

_{S20 V4.4 V0.4 V0.44 V}

⇒ A coaxial RF cable has a characteristic impedance of 50 Ω and C equal to 40 pF/m. The inductance is

1 μ H/m

10 μ H/m

0.1 μ H/m

0.01 μ H/m

⇒ A master slave flip-flop has the characteristics that

change in the I/P immediately reflected in the O/P

change in the O/P occurs when the state of the master is affected

change in the output occurs when the state of the slave is affected

both the master and the slave states are affected at the same time

⇒ It is desired to reduce the reflection at an air porcelain by use of 7/4 plate (for Porcelain μ = 40, and ε

_{r}= 7). The thickness of the polystyrene plate required at 10 GHz will be

5.039 cm

50.39 cm

0.5039 cm

0.05039 cm

⇒ Read the following statements about 8085

`RAL`

instruction rotates`ACC`

contents left by 1 bit- When
`RAL`

instruction is executed once the binary number gets doubled `STC`

means set`CY`

to 1

1 and 2 only

1, 2 and 3 only

1, 2 and 4 only

1 and 4 only

⇒

Match the following:

List I (Library function in Pascal) | List II (Type of argument) | ||
---|---|---|---|

A. | ROUND X | 1. | X in radians |

B. | ABS X | 2. | X real |

C. | SQR X | 3. | X real or integer |

D. | SIN X |

A-2, B-3, C-3, D-1

A-2, B-3, C-1, D-3

A-3, B-2, C-2, D-1

A-2, B-3, C-2, D-1

⇒ The characteristic impedance of coaxial cable is about

1000 ohm

500 ohm

250 ohm

75 ohm

⇒ The number of possible colours with a 4 line digital input monitor are

4

16

64

2

⇒ If a function Z(

*s*) has a pole at infinity, then

the degrees of numerator and denominator are equal

the degree of numerator is one higher than that of denominator

the degree of denominator is one higher than that of numerator

the difference between the degrees of numerator and denominator is 0 or 1

⇒ The frequencies in ultra high frequency range are propagated by means of __________ waves

surface

ground

sky

space

⇒ If

*t*is the pulse width, Δ

_{p}*is the propagation delay,*

_{t}*T*is period of pulse train then the following condition can avoid the race around condition

*t*= Δ

_{p}*t*= T

2

*t*> Δ

_{p}*t*> T

*t*< Δ

_{p}*t*< T

*t*< Δ

_{p}*t*< T

⇒ The number of inputs and outputs of a full adder are

3 and 2 respectively

2 and 3 respectively

4 and 2 respectively

2 and 4 respectively

⇒ In an

*n*channel JFET, V

_{GS}= V

_{GS(off)}. Then

I

_{D}is zero

I

_{D}may be zero or positive

I

_{D}is positive

I

_{D}may be zero or negative

⇒ For the control system in the given figure, the value of K for critical dampin

1

5.125

6.831

10

⇒ At room temperature the number of conducting electrons in an intrinsic semiconductor

is almost equal to the number of valence electrons

is about half the number of valence electrons

is small as compared to the number of valence electrons

is a very small fraction of the number of valence electrons