Test 9 Flashcards
What early device was developed to store electric charge?
Leyden jar
What is the general term for a device that transforms the energy of an electric current into another useful form of energy?
load
What is the SI unit of resistance?
ohm
What device consists of one or more electrochemical cells connected in series to produce a single source of current?
battery
What device converts pulses of electricity into sound waves?
loudspeaker
What communication device uses electromagnets to reproduce messages by means of audible clicks?
telegraph
What is a material that allows current to flow through it with no resistance?
superconductor
Who built the first electrostatic generator?
Otto von Guericke
What is the transfer of an electric charge by direct contact between objects?
conduction
What device converts absorbed sunlight directly into electricity?
photovoltaic cell
What type of generator works by passing a conducting fluid through a magnetic field?
magnetohydrodynamic generator
What is an electric field with even strength throughout?
uniform
What is the method of magnetism in which an object is permanently magnetized by stroking a magnet against the object?
magnetizing by contact
What is a semiconductor device that produces light when a direct current is applied?
light-emitting diode
What is the line connecting all points where a compass needle points true north?
agonic
What is the imaginary line that circles Earth halfway between the two magnetic poles?
magnetic equator
What is the final attraction force between two charged objects when the distance is reduced to 1/5 of the original distance?
25 times the original force
What is a small, relatively inexpensive computer designed for use by one user at a time?
personal computer
What is a large, extremely powerful computer designed for rapidly performing complex calculations?
supercomputer
What allows a computer to communicate with the outside world or a user to communicate with the computer?
input/output device
What part of a computer controls all other systems of the computer?
central processing unit
What is the largest computer network?
internet
What is a single chip that contains a complete CPU?
microprocessor
What is a collection of programs that contain instructions for displaying words and images on the screen for a user?
operating system
What type of computer memory is used for temporary storage?
RAM
What is the SI unit of electric charge?
coulomb
What are the actual physical components of a computer called?
hardware
What is the smallest directly accessible unit of data in a computer?
byte
What are the imaginary lines that indicate the direction and strength of a magnetic field called?
lines of flux
What is the electrostatic method of reproducing images on paper?
xerography
What is an electrical switch operated by an electromagnet called?
relay
What process produces an electric current in a vacuum using a heated cathode?
thermionic emission
What are pieces of information stored in computers called?
data
electronic device that processes information using electrical circuits
computer
produces a single binary output based on one or more binary inputs
logic gate
uses a narrow strip of metal in a protective, insulated case to limit current through a circuit
fuse
electrical device designed to add resistance to a circuit
resistor
uses electromagnetic induction to produce electricity
generator
produces a strong magnetic field when electricity passes through it
electromagnet
simple device that converts electricity to back-and-forth motion
solenoid
semiconductor device that can perform the same functions a vacuum-tube triode, such as acting as a switch and amplifying weak signals
transistor
increases or decreases the voltage of an alternating current using electromagnetic induction
transformer
The stored information and set of instructions that direct a computer to perform certain tasks is the _______.
software
The rate of charge flow is called _______.
current
The branch of the study of electricity that deals with the behavior and motion of electrons in a vacuum or in semiconductors is ______.
electronics
The process of replacing atoms of a semiconductor with atoms of another element is called ______.
doping
What is a simple vacuum tube consisting of three electrodes?
triode
What are large computers designed to store and retrieve vast amounts of information?
mainframes
What type of data can have any possible value within a specified range?
analog
The positive terminal of a voltaic or storage cell contacts the cell’s ______.
cathode
What number system is based on powers of sixteen?
hexadecimal
What is a semiconductor that lacks electrons?
p-type
What type of electrochemical cell is not designed to be recharged?
voltaic
The most common type of transistor used today is the _______ transistor.
field-effect
What was America’s first mass-produced computer?
UNIVAC I
Substances that can be easily magnetized are considered magnetically ______.
soft
