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Q1. | The temperature of cathode is increased from 2500K to 2600K. The increase in thermionic emission current is about |

A. | 0.001 [Wrong Answer] |

B. | 0.04 [Wrong Answer] |

C. | 0.5 [Wrong Answer] |

D. | 1.5 [Correct Answer] |

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Explanation:-
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**Also Read Similar Questions Below :**

⇒ With 2's complement representation, the range of values that can be represented on the data bus of an 8 bit microprocessor is given by

-128 to 127

-128 to +128

-127 to 128

-256 to 256

⇒ If

*x*

*= a*

_{k}*and*

^{k}*k*&l

TRUE

FALSE

⇒ Two coils X of 1000 turns and Y of 2000 turns are placed such that 60% of the flux produced by coil X links coil Y. A current of 1 A in coil X produces 0.1 wb flux. The mutual inductance between coils is

0.12 H

0.08 H

0.06 H

0.04 H

⇒ Consider the following statements about expressing real constants in exponential form in C

- The mantissa and exponent are separated either by e or E.
- The mantissa and exponent may have positive or negative sign.
- Default sign of mantissa is positive.
- Default sign of exponent is negative.

1 only

1 and 4 only

1, 3 and 4 only

4 only

⇒ In an SSB transmitter one is most likely to find

class C audio amplifier

tuned modulator

class B RF amplifier

class AB power amplifier

⇒ A rectangular wave guide is designed to propagate at the dominant mode TE

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4 cm, 2 cm

8 cm, 4 cm

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⇒ In which of the following 8085 instructions is the 8 bit number in accumulator adjusted to form two four bit BCD numbers

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`DAA`

`DCX `*rp*

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⇒ A Hartley oscillator is used for generation

very low frequency oscillation

radio frequency oscillation

microwave oscillation

audio-frequency oscillation

⇒ In using Nyquist stability criterion it is not necessary to determine closed loop poles.

TRUE

FALSE

⇒ A

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400.94 Ω

562.94 Ω

502.80 Ω

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⇒ For global communication, the number of satellites needed is

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⇒ For the circuit shown in the figure, what is the frequency of the outpu

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audio power amplifier

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compressor amplifier

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⇒ In an op-amp differentiator

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the amplitude of output is proportional to input

output occurs when input is finite and constant

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⇒ For a flexible cable, most suitable insulation is

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⇒ The transient currents are due to

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⇒ An

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^{0}/V-

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^{-19}coulomb, then the resistance of the bar is

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10

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⇒ Coupling and bypass filters can be a source of

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none of the above

⇒ In an LC filter, the ripple factor,

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has the lowest value

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⇒ Logic hardware is available only in NAND and NOR.

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⇒ In a 7 segment LED display, the minimum number of segments is activated when the input decimal number is

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⇒

**Assertion (A):** A photovoltaic cell is greatly affected by temperature.

**Reason (R):** Both germanium and silicon can be used for photovoltaic cells.

Both A and R are true and R is correct explanation of A

Both A and R are true but R is not correct explanation of A

A is true R is false

A is false R is true

⇒ From an

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⇒ A rectangular waveguide of internal dimensions (

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*b*= 3) is to be operated in TE

_{11}mode. The minimum operating frequency is

6.25 GHz

6.0 GHz

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⇒ Microwave signals follow the curvature of the earth and the phenomenon is known as

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duct propagation

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⇒ A rectangular waveguide having TE

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⇒ In a combination limiter with sinusoidal input voltage the output wave can be nearly square.

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FALSE