IFC page 5

tidirecu's version from 2016-06-21 19:19


Question Answer
When you view an electron tube and its socket connection from the bottom, in what direction are (a) the pins of the tube and (b) the pins of the socket numbered?(a) Clockwise (b) Clockwise *
Electron tubes are identified by a number preceded by which of the following letter designations?V *
The getter in an electron tube serves what purpose?It helps to produce a better vacuum
An electron tube is operated at 300 volts and a plate current of 60 milliamperes. To avoid being damaged, the tube must have what minimum plate dissipation rating?18 watts *
Under which of the following conditions can a tube be considered operating beyond its peak inverse voltage rating?When current flows from the plate to the cathode *
Why does control grid voltage of a triode exercise greater control than plate voltage over conduction of the tube?The grid is closer to the cathode than the plate *
An atom consists ofOne nucleus and one or more electrons Protons, electrons, and neutrons
The nucleus of an atom is made up ofProtons and neutrons
Valence electrons areIn the most distant orbit from the nucleus
A positive ion is formed whenA valence electron breaks away from the atom
The most widely used semiconductive material in electronic devices isSilicon
The difference between an insulator and a semiconductor isA wider energy gap between the valence band and the conduction band The number of free electrons The atomic structure
The energy band in which free electrons exist is the Conduction band
In a semiconductor crystal, the atoms are held together by The interaction of valence electronsForces of attraction Covalent bonds
The atomic number of silicon is14
The atomic number of germanium is 32
The valence shell in a silicon atom has the number designation of3
Each atom in a silicon crystal hasEight valence electrons, four of its own and four shared
Electron-hole pairs are produced byThermal energy
Recombination is whenAn electron falls into a hole
The current in a semiconductor is produced byBoth electrons and holes
In an intrinsic semiconductor, The free electrons are thermally producedThere are as many electrons as there are holes
The process of adding impurity to an intrinsic semiconductor is calledDoping
A trivalent impurity is added to silicon to createA p-type semiconductor
The purpose of a pentavalent impurity is toIncrease the number of free electrons
The majority carriers in an n-type semiconductor areConduction electrons
Holes in an n-type semiconductor areMinority carriers that are thermally produced
A pn junction is formed by The boundary of a p-type and an n-type material
The depletion region is created byIonization Diffusion Recombination
The depletion region consists ofPositive and negative ions. No majority carriers
The term bias meansA dc voltage is applied to control the operation of the device
To forward-bias a diode,An external voltage is applied that is positive at the anode and negative at the cathode; An external voltage is applied that is positive at p region and negative at the n region
When a diode is forwardThe current is produced by both holes and electrons
Although current is blocked in reverse bias,There is a very small current due to minority carriers
For a silicon diode, the value of the forward- bias voltage typically Must be greater than 0.7 V
When forward-biased, a diodeConducts current
A diode is normally operated in The forward-bias region The reverse-bias region
The dynamic resistance can be important when a diode isForward-biased
The V-I curve for a diode showsThe voltage across the diode for a given current
Ideally, a diode can be represented by aSwitch
In the practical diode modelThe barrier potential is taken into account
In the complete diode model,The barrier potential is taken into account The forward dynamic resistance is taken into account The reverse resistance is taken into account
When a silicon diode is working properly in forward bias, a DMM is the diode test position will indicateApproximately 0.7 V
When a silicon diode is open, a DMM will generally indicate0 L
The average value of a half-wave rectified voltage with a peak value of 200 V is63.7 V
Which of the following limit(s) the frequency response of a transistor amplifier?The inductance The transistor The capacitance
What type of feedback is caused by inter- electrode capacitance?Negative *
What happens to capacitive reactance as frequency decreases?It increases *
What happens to inductive reactance as frequency increases?It increases *
What is the major factor that limits the high frequency response of an amplifier?Capacitance *
What components can be used to increase the high-frequency response of an amplifier?Inductors *
What determines whether a peaking component is considered "series" or "shunt"?The relationship of the component to the output signal path *
What is the arrangement of both "series" and "shunt" peaking components called?Combination