Test 8 Flashcards
Opposite charges accumulate in a cloud and on the ground, causing an electrostatic discharge called _______.
lightning
What type of electric generator uses a commutator?
DC
A group of cells arranged in a parallel has the same voltage as any single cell, but the maximum currents of all the cells are _____ together.
added
The _____ lamp is the most efficient lamp.
LED
What is the most common type of electrostatic generator in use today?
Van de Graaf
A(n) _______ lamp produces light by passing current through a narrow tube of gas.
fluorescent
A(n) ______ lamp produces light by heating a thin piece of wire.
incandescent
A metal-topped car is safe shelter in a storm because the charge passes _______ the outside surface of the car.
over
In a Leyden jar, charge is stored on foil lining the ______ of a glass jar.
inside
A ________ cell converts absorbed sunlight directly into electricity.
photovoltaic
What is the component within an electric motor that is a freely rotating electromagnet mounted on a shaft?
armature
What is the component of an AC electric generator that keeps its wires from twisting?
slip ring
What converts electricity into sound waves?
loudspeaker
What is designed to convert electricity into back-and-forth motion?
solenoid
What uses electromagnets to allow communication over long distances?
telegraph
What is an electrical switch operated by an electromagnet?
relay
The negative terminal of a voltaic cell is called the _______.
anode
What was the early device developed by Musschenbroek to store electric charge?
Leyden jar
The first electric light suitable for household use was the _______.
incandescent lamp
To boost the available voltage, electrochemical cells can be arranged in _______.
series
What is a device for protecting buildings and other structures from lightning strikes?
lightning rod
The ability of magnetism to convert mechanical motion into electric current is called _______.
electromagnetic induction
What is a device that increases or decreases the voltage of alternating current?
transformer
One or more electrochemical cells connected to terminals as a single source of current form a _______.
battery
What material glows when exposed to radiation?
phosphor
A permanent magnet used to provide a stationary magnetic field is called a _______.
field magnet
What natural electrostatic phenomenon, also known as corona discharge, is an accumulation of electrons around pointed objects that results in an eerie blue glow?
St. Elmo’s fire
What is the positive terminal of a voltaic cell called?
cathode
What system of communication uses a combination of long and short clicks to transmit messages over long distances?
Morse code
What is the general term for a device that produces static electricity?
electrostatic generator
What type of electric discharge lamp is filled with neon gas?
neon lamp
What type of electrochemical cell is not designed to be recharged?
voltaic cell
What is a device that uses electromagnetic induction to produce electricity?
electric generator
Who discovered that mechanical motion can produce electricity by magnetic force?
Michael Faraday
Who patented the telegraph?
Samuel Morse
Whose experiment demonstrated that lightning is caused by static electricity?
Benjamin Franklin
Who built the first electrostatic generator?
Otto von Guericke
What is a modern lamp that consists of a long, coiled tube and can be used in sockets designed for incandescent lamps?
CFL
Electric charge on an object always moves to the _______ of an object.
outside
What is the most important device for converting electricity into motion?
electric motor
What is an electrostatic method of reproducing images on paper?
xerography
What is a device in which a conducting fluid passes through a magnetic field at high speeds?
magnetohydrodynamic generator
What is a small AC generator that recharges a car’s battery and operates its electrical system while the car is running?
alternator
The semiconductor device that emits light when a direct electric current is applied is a __________.
light-emitting diode
In an electrostatic generator, the charge is most concentrated wherever the contour comes to a ______.
point
A transformer that decreases the voltage is a ________ transformer.
step-down