Automotive Electronics Practice Test Questions and Answers

Automotive Electronics Practice Test Questions and Answers A series circuit has three resistors of 4 ohms each. The voltage drop across each resistor is 4 volts. Technician A says that the source voltage is 12 volts. Technician B says that the total resistance is 18 ohms. Which technician is correct? Tech A Tech B Both Neither - Answer-Tech A A vehicle has four parking lights all connected in parallel and one of the bulbs burns out. Technician A says that this could cause the parking light fuse to blow (open). Technician B says that it would decrease the current in the circuit. Which technician is correct? Tech A Tech B Both Neither - Answer-Tech B EMILLECT 2024/2025 ACADEMIC YEAR ©2024 EMILLECT. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER, 2024 Page 2/33 As additional branches are added to a a parallel circuit, total circuit resistance ________. Remains the same Decreases Increases None of the above - Answer-Decreases Calculate the total resistance and current in a 12-volt parallel circuit with three resistors of 4 ohms, 8 ohms, and 16 ohms, using any one of the five methods (calculator suggested). What are the total resistance and current? 140 ohms (18 amps) 4 ohms (3.0 amps) 2.3 ohms (5.3 amps) 22 ohms (0.4 amps) - Answer-2.3 ohms If one branch of a parallel circuit loses continuity, the other branches will still each receive source voltage and ground. True False - Answer-True If the resistance and the voltage are known, what is the formula for finding the current (amperes)? EMILLECT 2024/2025 ACADEMIC YEAR ©2024 EMILLECT. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER, 2024 Page 3/33 I = E x R E = I x R R = E x I I = E / R - Answer-I = E / R In a series circuit, total circuit resistance is equal to the ________ of the resistance of all loads in the circuit. Sum Dividend Difference None of the Above - Answer-Sum Kirchhoff's law states that the voltage around a closed circuit is equal to the sum of the ________ across all the loads. Voltage drops Resistances Both A & B Neither A nor B - Answer-Voltage drops More electrical current will tend to flow through the branch of a parallel circuit with ________ resistance. EMILLECT 2024/2025 ACADEMIC YEAR ©2024 EMILLECT. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER, 2024 Page 4/33 Infinite Lowest Highest None of the Above - Answer-Lowest Technician A says that electronic calculators have a memory function that can be used to calculate resistance, current, and voltage values for a parallel circuit. Technician B says that components of a series-parallel circuit are separated to simplify calculations. Which technician is correct? Tech A Tech B Both Neither - Answer-Both The amperage in a series circuit ________. Is always less returning than leaving the battery. Is the same anywhere in the circuit. Is high at the beginning of the circuit and decreases as the current flows through the resistance. Varies in the circuit due to the different resistances. - Answer-Is the same anywhere in the circuit. EMILLECT 2024/2025 ACADEMIC YEAR ©2024 EMILLECT. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER, 2024 Page 5/33 The higher the resistance of a load in a series circuit, the __________ the voltage drops across that load. Less Equal More None of the above - Answer-More The sum of the voltage drops in a series circuit equals the ________. Resistance Source voltage Wattage Amperage - Answer-Source voltage The voltage for each branch of a parallel circuit is ________. Reduced by the resistance of loads in each branch Equal Increased by the resistance of loads in each branch None of the above - Answer-Equal EMILLECT 2024/2025 ACADEMIC YEAR ©2024 EMILLECT. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER, 2024 Page 6/33 Two light bulbs are wired in series and one bulb burns out (opens.) Technician A says that the other bulb will work. Technician B says that the current will increase in the circuit because one electrical load (resistance) is no longer operating. Which technician is correct? Technician A Technician B Both Technicians A and B Neither Technician A nor B - Answer-Neither A series circuit has three resistors of 6 ohms each. The voltage drop across each resistor is 4 volts. Technician A says that the source voltage is 12 volts. Technician B says that the total resistance is 18 ohms. Which technician is correct? Technician A only Technician B only Both Technicians A and B Neither Technician A nor B - Answer-Both Technicians A and B If a 12 volt battery is connected to a series circuit with three resistors of 2 ohms, 4 ohms, and 6 ohms, how much current will flow through the circuit? 1 ampere 2 amperes EMILLECT 2024/2025 ACADEMIC YEAR ©2024 EMILLECT. ALL RIGHTS RESERVED FIRST PUBLISH OCTOBER, 2024 Page 7/33 3 amperes 4 amperes - Answer-1 ampere A series circuit has two 10 ohm bulbs. A third 10 ohm bulb is added in series. Technician A says that the three bulbs will be dimmer than when only two bulbs were in the circuit. Technician B says that the current in the circuit will increase. Which technician is correct? Technician A only Technician B only Both Technicians A and B Neither Technician A nor B - Answer-Technician A only Technician A says that the sum of the voltage drops in a series circuit should equal the source voltage. Technician B says that the current (amperes) varies depending on the value of the resistance in a series circuit. Which technician is correct? Technician A only Technician B only Both Technicians A and B Neither Technician A nor B - Answer-Both Technicians A and B Four resistors are connected to a 12 volt battery in series. The values of the resistors are 10 ohms, 100 ohms, 330 ohms, and 470 ohms. Technician A says that th