Basic Electricity Flashcards
When charging current is applied to a nickel cadmium battery, the cells emit gas..
Toward the end of the charging cycle.
What is the purpose of the ground symbol used in electrical circuit diagrams?
To show that there is a return path for the current.
Transfer of electric energy from one circuit to another without the aid of electrical connections
is called induction.
A thermal switch, or thermal protector, as used in an electric motor, is designed to
Open the circuit to allow cooling.
What is commonly used as a rectifier in electrical circuits?
Diodes
What describes the combined resistive forces in an AC circuit?
Impedance
Typical application for zener diodes is as
a voltage regulator
What may result if water is added to a nickel-cadmium battery when it is not fully charged?
Excessive spewing can occur while charging.
A fully charged lead-acid battery will not freeze until extreme low temperatures are reached because..
most of the acid is in the solution.
The potential difference between two conductors which are insulated from each other is measured in ….
Volts
What factors strengthen a coil inductor?
Adding coils close together.
What will a voltmeter read when properly connected across a closed circuit that is powered on?
0 voltage
Foward biasing of a solid- state device will cause the device to
conduct
In an AC circuit, the effective voltage is
less than the maximum instantaneous voltage.
The basis for transformer operation in the use of alternating current is mutual
inductance
What is the basic unit of electrical quantity?
Coulomb
The presence of any small amount of potassium carbonate deposits on the top of nickel-cadmum battery cells in service is an indication of
normal operation
The working voltage of a capacitor in an ac circuit should be
at least 50% greater than the highest applied voltage.
What unit is used to express electrical power?
Watt
Unless otherwise specified, any values given for current or voltage in an ac circuit are assumed to be
effective values
What does the letter Q symbolize when measuring electrical charge?
Coulomb
When referring to an electrical circuit diagram, what point is considered to be at zero voltage?
The ground reference
The electrolyte of a nickel cadmium battery is highest when the battery is
in a fully charged condition
In nickel-cadmium batteries, a rise in cell temperature
causes a decrease in internal resistance
What is the opposition to the flow of ac produced by an electromagnetic field with generated back voltage called?
inductive reactance
A condition of improperly torqued cell link connections on a nickel-cadmium battery
heat or burn marks of hardware
A condition of improperly torqued cell link connections on a nickel-cadmium battery
heat or burn marks on hardware
In a P-N-P transistor application, the solid-state device is turned on when the
base is negative with respect to the emitter
What determines the amount of current which will flow through a battery while it is being charged by a constant voltage sourece
the state-of-charge of the battery
How can the state-of-charge of a nickel-cadmium battery be determined?
By a measured discharge
During discharge , nickel-cadmium batteries will show a lower liquid level than when at full charge because
the electrolyte becomes absorbed into the plates
The method used to rapidly charge a nickel-cadmium battery utilizes
constant voltage with varying current
The voltage drop in a circuit of known resistance is dependent on
the amperage of the circuit
Electrostatic fields are also known as
dielectric fields
what is the purpose of providing a space beneath lead-acid battery plates
to prevent sediment buildup from contacting the plates and causing a short circuit.
When calculating power in a reactive circuit, the true power is
less than the apparent power
capacitors are sometimes used in DC circuits to
smooth out slight pulsations in current/ voltage