Chapter 2 Flashcards
Conductors
3 or fewer electrons
insulator
5 or more electrons
semiconductor
four electrons
voltage
- defined as electrical pressure
- force that causes the movement of electrons in the conductor
ammeter
the instrument used to measure electrical current flow in a circuit
ohmmeter
an instrument used to measure the resistance to electrical flow
voltmeter
used to measure the voltage or electrical pressure through a circuit
jumper wires
connecting one end of the jumper wire to battery positive will give an excellent 12 volt power supply
-Can also be used to bypass individual wires connectors components or switches
test lights
- used when the technician needs to look for electrical power in the circuit
- limited because it does not display voltage though
- do not use to test computer control modules it may damage them
Logic probes
used to test computer modules
Current
defined as the rate of electron flow
Parallel Circuit
1) voltage applied to each parallel leg is the same
2) Voltage drop across each leg will be the same unless one leg has different resistances
3) total resistance of the parallel will always be less than its lowest resistance
4) current flow through the legs will be different if the resistances are different
5) The sum of the current in each leg EQUALS the total current of the parallel circuit
series circuit
1) total resistance is the sum of the resistance
2) current is the same at all points of the circuit
3) voltage drop across each resistance will be equal if the resistance values are the same
4) the voltage drop across each resistance will be different if the resistances are different
5) sum of all voltage drops equals source voltage (total voltage)
Series-Parallel Circuit
1) total resistance is the sum of the parallel circuit AND the series together (R1xR2/ R1+R2 AND series)
2) voltage drop over the parallel branch is determined by the resistance value of the series resistor
3) total amperage is the sum of the current flow through each parallel branch
4) amperage through each parallel branch id determined by the resistance in the branch
Ohms law
it takes 1a to push 1 volt through one ohm of resistance
Kirchoff’s law
1) algebraic sum of the currents entering and leaving a point must be zero
2) the algebraic sum of the voltage sources and voltage drop in a closed circuit must equal zero
If the number of ____________ and ______ are equal the atoms is ______________________-
Protons, electrons balanced
List 3 elements of electricity
- Electromagnetic force
- Ion
- balanced atoms
Electron theory
negative to positive
Conventional Theory
Positive to negative flow
voltage drop
when parts of the voltage are used up when the current is flowing over a resistance
A______ allows electricity to easily flow through it. An ________________ does not allow electricity to flow through it easily
conductor / insulator
for the electrons to move in the same direction there must be an _____________________ applied
electrical current or electric magnetic force
Which of the following methods can be used to form an electrical current? a) Magnetic induction B) chemical reaction C) Heat d) all of the above E) none of the above
D) all of the above
In a parallel circuit
a) total resistance is the sum of all of the resistances in the circuit
b) total resistance is less than the lowest resistor
c) amperage will decrease as more branches are added
d) all of the above
B) total resistance is less than the lowest resistor
All of the following are true concerning voltage drop except:
A) all of the voltage from the source must be dropped before it returns to the source
b) corrosion is not a contributor to voltage drop
c) voltage drop is the conversion of electrical energy into another energy form
d) voltage drop can be measured with a voltmeter
B) corrosion is NOT a contributor to voltage drop
Wattage is: A) a measure of the total electrical work being performed per unit of time B) P=RxA C)Both a and b D) neither a nor b
C) both a and b
which answer. is incorrect concerning a series circuit
a) total resistance is the sum of all of the resistances in the circuit
b) total resistance is less than the lowest resistor
c) amperage will decrease as more resistance is added
d) all of the above
B) total resistance is less than the lowest resistor
Which statement about electrical currents is correct?
a) alternating current can be stored in a battery
b) an alternating current is produced from a voltage and current that remain constant and flow in the same direction
C) direct current is used for most electrical systems on the automobile
d) direct current changes directions from positive to negative
C) direct current. is used for most electrical systems on an automobile
All of the following are true except:
a) if the resistance increase and the voltage remains the same the amperage will increase
b) ohms law can be stated as A=V/R
c) if the voltage is increased, amperage will increase
d) an open circuit does not allow current flow
a
which of the following statements are true:
a) an insulator is capable of supporting the flow of electricity through it
b) a conductor is not capable of supporting the flow of electricity through it
c) all of the above
d) none of the above
d
Technician A says testing with a voltmeter can determine the voltage drop across the headlights. Technician B says a voltmeter can determine if excessive resistance is in the circuit. Who is correct? A) Technician A only B ) Technician B only C) Both Technician A and B D) Neither Technician A nor B
C
According to Ohm’s Law, what is the resistance when 1 volt pushes 1 ampere of current through a conductor? 0 ohm 1 ohm 1 watt 1 coulomb
1 Ohm
The display of a DVOM is indicating 236 mV. Which of the following is the same as this value? You Answered 0.236 millivolts 0.236 volts 23.6 volts 0.000236 volts
.236 milivolts
Technician A says the conventional theory of current flow states that current flows positive to negative. Technician B says current flows randomly. Who is correct? Technician A only Technician B only Both Technician A and B Neither Technician A nor B
technician a
The ____ is a contract between the customer and the shop to have specified service performed.
work order
flat rate
service writer
ASE certification certificate
work order
Technician A says horizontial adjustment of an oscilloscope affects the time-per-division values. Technician B says changing the vertical adjustment of an oscilloscope affects the volts-per-division values. Who is correct? Technician A only Technician B only Both Technician A and B Neither Technician A nor B
both a and b
In a closed circuit with a capacitor, when will the current stop flowing?
a) When the voltage charge across the capacitor plates becomes less than the source voltage
b) When the voltage charge across the capacitor plates becomes equal to the source voltage
c) When the voltage charge across the capacitor plates becomes greater than the source voltage
d) When the voltage charge across the capacitor plates becomes equal to the resistance of the plates
b) when the voltage becomes equal
Technician A says the total amperage in a parallel circuit is equal to the sum of the individual branch circuits. Technician B says the amperage in a series circuit is the same anywhere in the circuit. Who is correct?
a) Technician A only
b) Technician B only
c) Both Technician A and B
d) Neither Technician A nor B
c) both technician a and b
The frame of the vehicle is normally attached to the positive battery post.
True
or
False
false its attached to the negative battery post
An individual who passes a particular ASE-certification examination becomes certified in that test area.
True
Or
False
True
