Physical Science 1120 Self Test
The problem of transmitting a human voice on a radio wave was solved by using ____________ radio waves
modulated
emit amber or green light
monochromatic CRTs
The semiconductor germanium becomes a negative, or ____________, semiconductor when it is doped with arsenic from VA Group
n-type
layer of insulating material
passivating layer
deflection yoke
performs scanning
The inside of a CRT screen is coated with rows of ______________
phosphorescent dots
components of a television screen
photocathode, target, camera tube
types of nuclear reactions
radioactive decay, fission, fusion
Nuclear ____________ is the emission of high-speed particles and electromagnetic radiation caused by the breakdown of unstable nuclei of certain elements
radioactivity
Name two radioactive elements
radium and polonium
cathode
receives video signal and emits electrons
device that converts AC to DC
rectifier
control grid
regulates intensity of flow of electrons
control rod
regulates rate of fission reaction
process in which a beam is moved back and forth across a screen
scanning
moderator
slows neutrons
The major disadvantage of _____________ radio is that other electromagnetic waves in the vicinity destructively interfere and produce static interference
AM
Voltage applied to the gate of a _____________ transistor controls current
field-effect
FET
field-effect transistor
components of a triode
filament, grid, plate
________________ substances emit energy in the form of visible light as electrons gradually fall to lower energy levels after they have jumped to a higher energy level because of absorbing ultraviolet light
fluorescent
focusing anode
focuses electrons into a narrow beam
Y
gamma ray
IC
integrated circuit
A np semiconductor, joined at a _____________, functions as a diode to control the flows of electricity
junction
Input current controls output current in a ______________ transistor
junction
single plate on which drawings are duplicated
mask
A ____________ radio wave is produced by impressing audio-frequency waves on a carrier wave
modulated
Input current controls output current in a _____ transistor
Junction
Transistor
Transfer resistor
(2)He(4)
alpha particle
Nuclear radiation includes _____________ particles, __________ particles, and _________ rays
alpha, beta, gamma
A triode act both as a rectifier and as an ______________
amplifier
More scientific discoveries have been made during the last 140 years because modern scientists have a better understanding of the __________ and its _________
atom, structure
(-1)B(0)
beta particle
Germanium becomes a ____________, or p-type, semiconductor when it is doped with boron from the IIIA Group
positive
silicon wafer of p-type semiconductor material
substrate
A fusion reaction requires intense ___________ and ___________
temperatures, pressures
___________ emission is the emission of electrons from a hot, glowing object
thermionic
AM
amplitude modulation
The image on a color screen appears to be a solid picture because the dots are very ___________, the scanning process is extremely ____________, each dot tends to glow even after the bean has passed over it, and our eyes continue to see light even after it has disappeared
tiny, fast
primary components of modern electronic devices
transistor, integrated circuit
electronic device containing three electrodes
triode
evacuated glass bulb in which current flows across vacuum
vacuum tube
spot etched off wafer by acid solution
window
Voltage applied to the gate of a ____ transistor controls currents
Field-effect
accelerating anode
speeds up electrons and shoots them toward screen
The ____________ effect is the glow caused by thermionic emission
Edison
An n-type semiconductor contains a _____________ electron; a p-type semiconductor contains a ____________
free, "hole"
FM
frequency modulation
_______________ could satisfy the energy needs of the world if it ever becomes possible to produce it efficiently
fusion energy
device in which electric current causes gases to emit light
gas-discharge tube
Joseph John Thomson discovered that electrons had a negative change because they were _____________ by positive electrostatic fields and _____________ by negative ones
attracted, repelled
B
beta particle
emit white light
black-and-white CRTs
CRT
cathode ray tube
emit red, green and blue light
color CRTs
core
contains uranium fuel
components of an electron gun
control grid, 2 anodes, cathode
A television viewer may lose some of his imagination and ____________
creativity
electronic device containing two electrodes
diode
________________ is the science that deals with the emission, behavior, and control of electrons
electronics
layer of n-type semiconductor
epitaxial layer
Integrated circuits are less _____________ and ___________ in size than other solid-states components
expensive and smaller
Transistors are less ____________, more ____________, and ____________ in size than vacuum tubes
expensive, energy efficient, smaller