Unit 6 Physics
Transformer
A _____ is a device that enables you to easily change the voltage of a supply.
Relay Switch
A _____ is a device that enables you to use a small current to control a larger current.
Fuse
A _____ is a protective device that burns in two when overloaded.
Circuit Breaker
A _____ is a protective device that prevents circuit overloads from causing fires.
Nonpolluting and Inexhaustible
A big advantage of wind power is that it is polluting.
North
A compass' needle points to the ___________.
Magnet
A magnet's south pole is attracted to the north pole of another _______ due to an attraction called magnetism.
Battery
receives electric current from the brushes
Wire Loop
receives electric current from the brushes creating a electromagnet that is seeks the opposite pole of the permanent magnet
Iron
If a conducting wire is wrapped into a coil around a(n) _______ core, the wire's current magnetizes it, and you create an electromagnet.
Photo Voltaic
If a device produces electric current directly from the sunlight, then it is hydroelectric.
Indoors
If lightning is in the area, the best practice is to go ___________ or get inside a car.
Transformers
It is easy to step-up or step-down the voltages of AC current via __________.
Stator
An AC electric generator or motor has a stationary part called the _______.
Amperes or Amps
An ammeter measures current in _____.
Ammeter
An electric current can be measured by this instrument:
Burns
Automobile electrical systems can cause severe ____________ if shorted.
Resistance
Energy loss in power lines is primarily due to ________________.
Commutator
Every half revolution of the wire loop in a in our simple DC motor, the ________ reverses the current, thereby changing the direction of the magnetic field of a DC motor's wire loop.
Inexhaustible
Four sources of energy that are undergoing development currently are wind power, solar power, hydro-power, and nuclear fusion because they are exhaustible.
Magnet
In a simple DC electric motor, the current in the _______ reverses each half cycle.
Torque
In a simple DC motor, ________ is produced by the loop's constant rotation.
Battery
In a simple DC motor, a ________ provides a DC power.
Heat
In early incandescent light bulbs, 98% of the energy was converted into
AC
In our country's history, there was a battle between whether we could use AC or DC power; ____ power's advantages were responsible for its use today.
Cheaper
In the incandescent light bulb, a filament was __________, safer and more pleasant alternative to the arc lamp.
Charges
Moving _________ create an electric current.
Thomas Alva Edison
Nikola Tesla invented the first practical and commercially feasible light bulb (1879).
Alternating
Nikola Tesla's understanding of direct currents that were out of phase caused a rotating magnet field is considered to be one of the ten greatest discoveries of all times.
Hydroelectric power
Photoelectricity is generated by the kinetic energy of falling water to drive electric generators.
Geothermal
Power derived from hot rocks is hydroelectric energy production.
Magnetic
The ___________ field in a DC motor's magnet deflects or repulses the wire loop's magnetic field created and as a result, makes the loop rotate.
Incandescence
The emission by a body of visible light caused by a high temperature is called _____.
Arc
The first electric lights used a(n) _________ .
Electromagnetism
The reason an electric current can create a magnetic field is due to the phenomenon of ___________.
Thomas Alva Edison
The scientist, who at one point, had a monopoly on the electrical power delivery system by promoting the use of DC systems, invented the first incandescent light bulb, and owned General Electric
Damp
Use a GFCI outlet when using electrical devices in ____________ conditions.
Voltmeter
Voltage can be measured by this instrument:
AC
Voltage is easy to convert from one to another.
AC
Voltage is more difficult to convert from one to another.
Nikolas Tesla
_____ was a Croatian who moved to America and made significant advances to the AC system.
AC
ability to carry power at higher voltage and lower current reducing loss due to line resistance
Galvanometer
an instrument made of a wire loop between a permanent, stationary magnet's poles that detects the presence and strength of small electric currents