Ncatt (Aet) Study Guide For Exams

NCATT (AET) STUDY GUIDE FOR EXAMS |\ |\ |\ |\ |\




Ampere ( A, amp, amperage) - CORRECT ANSWERS ✔✔•
|\ |\ |\ |\ |\ |\ |\ |\ |\



Unit of measurement used to express the flow of
|\ |\ |\ |\ |\ |\ |\ |\ |\



electrons (electrical current) |\ |\




• One ampere is a rate of flow of one coulomb (6.28
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



billion - billion electrons) passing a given point in an
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\



electrical circuit per second |\ |\ |\




• In mathematical problems amperage is expressed by
|\ |\ |\ |\ |\ |\ |\ |\



the letter "I"
|\ |\




Battery - CORRECT ANSWERS ✔✔• A device consisting of
|\ |\ |\ |\ |\ |\ |\ |\ |\



a number of primary voltaic cells (cells that cannot be
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\



recharged) or secondary cells (cells that can be |\ |\ |\ |\ |\ |\ |\ |\



recharged) connected in series to obtain a desired DC |\ |\ |\ |\ |\ |\ |\ |\ |\



voltage
• A battery stores chemical energy and converts the
|\ |\ |\ |\ |\ |\ |\ |\ |\



energy into electrical form |\ |\ |\




• Aircraft storage batteries are generally rated at 12 or 24
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\



volts
|\




Capacitor - CORRECT ANSWERS ✔✔• Electrical device |\ |\ |\ |\ |\ |\ |\



used to store charge and energy in the form of an
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



electrostatic field |\

,• A capacitor is a device made of two parallel conductors
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



separated by an insulator |\ |\ |\




Conductor - CORRECT ANSWERS ✔✔• Common building |\ |\ |\ |\ |\ |\ |\



block of electrical circuits that easily permits the
|\ |\ |\ |\ |\ |\ |\ |\



movement of electrons from an electrical source to a load |\ |\ |\ |\ |\ |\ |\ |\ |\



and back to the electrical source with a minimum of
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



resistance.
• A conductor's resistance depends on such factors as
|\ |\ |\ |\ |\ |\ |\ |\ |\



cross sectional area, length, temperature, and conductor
|\ |\ |\ |\ |\ |\ |\



material.


Coulomb - CORRECT ANSWERS ✔✔• Basic unit of
|\ |\ |\ |\ |\ |\ |\ |\



electrical quantity. |\




• A coulomb is equal to 6.28 billion - billion electrons
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



(6.28 x 10 to the 18th)
|\ |\ |\ |\ |\




Current - CORRECT ANSWERS ✔✔• The flow of electrons
|\ |\ |\ |\ |\ |\ |\ |\ |\



through a conductor is known as current flow.
|\ |\ |\ |\ |\ |\ |\




• The rate of current flow is measured in amperes.
|\ |\ |\ |\ |\ |\ |\ |\ |\




Direct Current (DC) - CORRECT ANSWERS ✔✔• A flow of
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\



electrons in one direction throughout an electric circuit
|\ |\ |\ |\ |\ |\ |\ |\



with constant voltage and current.
|\ |\ |\ |\

,• Direct current is caused by a constant difference of
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\



potential, both negative and positive. |\ |\ |\ |\




Electron - CORRECT ANSWERS ✔✔• Negatively charged
|\ |\ |\ |\ |\ |\ |\



subatomic particles that are located and travel around|\ |\ |\ |\ |\ |\ |\ |\



(orbit) the nucleus in an imaginary sphere or shell at the
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



speed of light (186,000 miles/second)
|\ |\ |\ |\




• Electrons are involved in the conduction of electricity.
|\ |\ |\ |\ |\ |\ |\ |\




EMF (electromotive force) - CORRECT ANSWERS ✔✔• The
|\ |\ |\ |\ |\ |\ |\ |\



force that causes electrons to flow through a conductor.
|\ |\ |\ |\ |\ |\ |\ |\




• This force is abbreviated e.m.f.
|\ |\ |\ |\ |\




• The unit of measurement for eletromotive force is the
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\



volt.
• In mathematical problems voltage is expressed by the
|\ |\ |\ |\ |\ |\ |\ |\ |\



letter "E". |\




Farad - CORRECT ANSWERS ✔✔• Basic unit of
|\ |\ |\ |\ |\ |\ |\ |\



capacitance |\




• One farad holds one coulomb under a pressure of one
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



volt.


Henry (H) - CORRECT ANSWERS ✔✔• Basic unit of
|\ |\ |\ |\ |\ |\ |\ |\ |\



measurement for inductance of an electrical coil |\ |\ |\ |\ |\ |\ |\

, • One (1) henry is the inductance of a coil when a change
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



of current of one (1) ampere per second induces an e.m.f.
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\



of one (1) volt
|\ |\ |\ |\




• In mathematical problems inductance is expressed by
|\ |\ |\ |\ |\ |\ |\ |\



the symbol "L". |\ |\




Inductor - CORRECT ANSWERS ✔✔• Coil or other device|\ |\ |\ |\ |\ |\ |\ |\ |\



used to introduce inductance into a circuit.
|\ |\ |\ |\ |\ |\ |\




• An inductor is a winding, or coiling, of multiple turns of
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



wire


Insulator - CORRECT ANSWERS ✔✔• Material or device |\ |\ |\ |\ |\ |\ |\ |\



used to prevent the passage of heat, electricity, or sound
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\



from one medium to another. |\ |\ |\ |\




Left hand rule - CORRECT ANSWERS ✔✔• Refers to
|\ |\ |\ |\ |\ |\ |\ |\ |\



electrical
• This rule is for determining the direction of movement
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\



of a current - carrying conductor in a magnetic field
|\ |\ |\ |\ |\ |\ |\ |\ |\




Magnetic Permeability - CORRECT ANSWERS ✔✔• |\ |\ |\ |\ |\ |\



Measure of ease that lines of flux travel through a|\ |\ |\ |\ |\ |\ |\ |\ |\ |\



material