Chapter 11 Flashcards
Who invented the first electrostatic generator?
Otto von Guericke
What is a device that produces electricity?
electrostatic generator
Who developed the Wimshurst machine?
James Wimshurst
What is a machine which uses two rotating disks to increase a charge through induction?
Wimshurst machine
What is a high-voltage electrostatic generator that is the most common type in use today?
Van de Graaff generator
Where does the electric charge move to on the charged object?
to the outside of the charged object, never the inside
Where is the charge more concentrated?
Wherever the contour is and comes to a point
What is the large discharge of static electricity between the ground and a cloud during a thunderstorm?
lighting
What is a device that protects buildings and other structures from lighting strikes by directing the charge away from easily damaged materials?
lightning rod
What is an eerie blue glow that appears around pointed objects during storms; is actually electrostatic phenomenon called corona discharge?
St. Elmo’s Fire
What is an early device that used a foil-lines jar to store an electric charge?
Leyden jar
What is a device used to store a static electric charge?
capacitor
What is the method of reproducing images on paper using electrostatics?
xerography
What uses friction from the passing air to obtain a negative charge?
electrostatic air filters
What is an electric lamp that produces light by heating a thin wire called a filament to a high temperature?
incandescent lamp
What is an electric discharge lamp that passes an electric current through a tube containing a low-pressure mixture of mercury vapor and argon to produce ultraviolet light, which is converted to visible light by a phosphor on the inner surface on the tube?
fluorescent lamp
What is a fluorescent lamp that used a coiled tube to be about the size of a regular incandescent bulb and is designed to fit in sockets designed for incandescent bulbs?
compact fluorescent lamp
What is an electric discharge lamp filled with neon gas?
neon lamp
What is a semiconductor that emits visible light what a direct current is applied?
light-emitting diode (LED)
What is a device that produces back-and-forth motion?
solenoid
Who was an American inventor, scientist, and artist best known for his invention of the telegraph?
Samuel Morse
What is a device used for communication over long distances by means of electromagnets that essentially consists of a switch (key), a long wire, and an electromagnet as the receiver?
telegraph
What is an electrical switch operated by an electromagnet?
relay
What is a device used for converting electricity into motion?
electric motor
What is a device that converts pulses of electricity into sound waves?
loudspeaker
In which type of motor does the direction of the current in the armature each half-term cause the armature to rotate continuously?
DC motor
What is the device in a DC motor that causes the rotation of the armature to be possible and allows for the continued repulsion of the poles?
commutator
What is similar to a DC motor but does not need a commutator because alternating current already alternates direction?
AC motor
In an AC motor, what is the commutator replaced by?
a simple pair of slip rings
What is a non-rechargeable electrochemical cell in which a chemical rection produces electricity?
voltaic cell
What is the current-producing electrochemical cell that can be recharged with electricity from an outside current source?
storage cell
What is the electrode through which the electrons exit an electrochemical cell; the negative terminal?
anode
What is the electrode through which electrons enter an electrochemical cell; the positive terminal?
cathode
What is one or more electrochemical cells connected to terminals as a single-source of current?
battery
How must the cells be arranged in order to boost the voltage?
series
How must the cells be arranged in order to boost the maximum available current?
parallel
What type of motion can directly produce electric current by the magnetic force?
mechanical motion
What is the ability of magnetism to convert mechanical motion into electric current?
electromagnetic current
How can the strength of an electromagnetically induced current be increased?
- by increasing the number of turns in the coil
-by moving the magnet faster
-by increasing the strength of the magnet
-by changing out the core
What is a device that uses electromagnetic induction to produce electricity?
generator
What is an AC generator extremely similar to?
an AC electric motor
What is the primary difference between a motor and a generator?
a motor uses electricity to produce motion and a generator uses motion to produce electricity
What is a device that detects and measures very small electric current?
galvanometer
Who discovered that mechanical motion can directly produce electric current by the magnetic force?
Michael Faraday
What is a device in which a conducting fluid passes through a magnetic field at high speed to generate electricity?
magnetohydrodynamic generator
Does a generator create energy out of nowhere?
no
How does a generator create energy if in does not create energy out of nowhere?
it converts motion into electrical energy
What is a device that increases or decreases the voltage of alternating current using electromagnetic induction?
transformer
Who is credited with inventing a capacitor (Leyden jar)?
Musschenbroek
