Tüm alıştırma soruları

5215 soru

Soru 961Soru →

A benchtop DC power supply delivers 45 V45\text{ V} across a fixed resistor in a test circuit. A series ammeter measures a steady current flow of 5 A5\text{ A} through the component. What is the electrical resistance of the resistor?

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Cevap: 9 Ω9\ \Omega

Cevap

9 Ω9\ \Omega
According to Ohm's Law, electrical resistance is equal to the voltage across a component divided by the current passing through it (R=V/IR = V / I). Substituting 45 V45\text{ V} and 5 A5\text{ A} yields R=45/5=9 ΩR = 45 / 5 = 9\ \Omega.

Adım Adım Çözüm

1
Identify the given circuit parameters and standard Ohm's Law formula
Voltage V=45 VV = 45\text{ V}, Current I=5 AI = 5\text{ A}, Ohm's Law: V=I×RV = I \times R
Ohm's Law defines the relationship between potential difference, current flow, and resistance in a DC circuit.
2
Rearrange Ohm's Law to solve for resistance (RR)
R=VIR = \frac{V}{I}
Dividing both sides of V=I×RV = I \times R by current isolates the unknown resistance.
3
Substitute the given values into the formula and evaluate
R=45 V5 A=9 ΩR = \frac{45\text{ V}}{5\text{ A}} = 9\ \Omega
Dividing 45 by 5 yields the exact resistance value in ohms.

Anahtar Kavram

Ohm's Law Resistance Calculation (R=V/IR = V / I)
Tahmini Süre:45s
Soru 962Soru →

An industrial control panel utilizes a direct-current bus to power three parallel branches. Branch 1 contains a 15 Ω15\ \Omega resistor, Branch 2 contains a 30 Ω30\ \Omega resistor, and Branch 3 contains a 10 Ω10\ \Omega resistor. If an ammeter connected in Branch 2 measures a current of 3 A3\text{ A}, what is the total current delivered by the power supply to the entire circuit?

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Cevap: 18.0 A18.0\text{ A}

Cevap

18.0 A18.0\text{ A}
The supply voltage across the parallel circuit is constant. Using Branch 2, V=3 A×30 Ω=90 VV = 3\text{ A} \times 30\ \Omega = 90\text{ V}. The remaining branch currents are I1=90 V/15 Ω=6 AI_1 = 90\text{ V} / 15\ \Omega = 6\text{ A} and I3=90 V/10 Ω=9 AI_3 = 90\text{ V} / 10\ \Omega = 9\text{ A}. Summing all three branch currents yields Itotal=6 A+3 A+9 A=18 AI_{\text{total}} = 6\text{ A} + 3\text{ A} + 9\text{ A} = 18\text{ A}.

Adım Adım Çözüm

1
Calculate the common supply voltage across the parallel circuit using Ohm's Law on Branch 2.
V=I2×R2=3 A×30 Ω=90 VV = I_2 \times R_2 = 3\text{ A} \times 30\ \Omega = 90\text{ V}
In a parallel circuit, the voltage drop across every individual branch is equal to the total supply voltage.
2
Determine the current flowing through Branch 1 and Branch 3 using the common voltage of 90 V90\text{ V}.
I1=90 V15 Ω=6 AI_1 = \frac{90\text{ V}}{15\ \Omega} = 6\text{ A} and I3=90 V10 Ω=9 AI_3 = \frac{90\text{ V}}{10\ \Omega} = 9\text{ A}
Current in each individual branch is determined by dividing the constant branch voltage by that branch's resistance.
3
Apply Kirchhoff's Current Law to sum the currents of all parallel branches.
Itotal=I1+I2+I3=6 A+3 A+9 A=18 AI_{\text{total}} = I_1 + I_2 + I_3 = 6\text{ A} + 3\text{ A} + 9\text{ A} = 18\text{ A}
The total current leaving the power supply equals the sum of the individual branch currents in a parallel circuit.

Anahtar Kavram

In a parallel circuit, voltage remains constant across all branches (Vtotal=V1=V2=V3V_{\text{total}} = V_1 = V_2 = V_3), and total circuit current is the sum of all individual branch currents (Itotal=I1+I2+I3I_{\text{total}} = I_1 + I_2 + I_3).

Alternatif Yöntem

Calculate total equivalent resistance first: 1Req=115 Ω+130 Ω+110 Ω=2+1+330=630=15 Ω\frac{1}{R_{\text{eq}}} = \frac{1}{15\ \Omega} + \frac{1}{30\ \Omega} + \frac{1}{10\ \Omega} = \frac{2 + 1 + 3}{30} = \frac{6}{30} = \frac{1}{5\ \Omega}, giving Req=5 ΩR_{\text{eq}} = 5\ \Omega. With V=90 VV = 90\text{ V}, total current is Itotal=VReq=90 V5 Ω=18 AI_{\text{total}} = \frac{V}{R_{\text{eq}}} = \frac{90\text{ V}}{5\ \Omega} = 18\text{ A}.
Tahmini Süre:1m 30s
Soru 963Soru →

While troubleshooting a direct-current (12 V12\text{ V}) automotive auxiliary circuit, a technician observes that the branch fuse blows immediately every time the power switch is closed. Which of the following electrical faults is the most probable cause of this issue?

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Cevap: A short circuit directly to ground before the load

Cevap

A short circuit directly to ground before the load is the most probable cause because it creates a near-zero resistance path that draws excessive current, exceeding the fuse rating.
A short circuit directly to ground creates a zero- or near-zero-resistance bypass around the intended load. According to Ohm's law (I=VRI = \frac{V}{R}), as resistance approaches zero, the circuit current rapidly exceeds the protective fuse's current rating, instantly melting the fuse link when the switch is closed.

Adım Adım Çözüm

1
Analyze the observed symptom and the operational role of a fuse.
A fuse is an overcurrent protection device designed to melt and open when current exceeds its specified ampere rating.
Understanding why fuses blow establishes that the root cause must be excessive current draw.
2
Apply Ohm's law (I=VRI = \frac{V}{R}) to evaluate how each potential fault affects circuit current.
To produce massive current (II) from a constant 12 V12\text{ V} source, the total resistance (RR) must drop close to 0 Ω0\,\Omega.
Ohm's law dictates an inverse relationship between resistance and current.
3
Identify the circuit condition that causes near-zero resistance.
A short circuit bypasses the normal load resistance directly to ground, causing an instantaneous current spike that blows the fuse.
Open circuits and high-resistance connections reduce or eliminate current flow rather than increasing it.

Anahtar Kavram

A short circuit provides an unintended low-resistance bypass path that causes current to surge above safe levels, blowing protective fuses.
Tahmini Süre:45s
Soru 964Soru →

A step-up transformer utilized in an industrial ignition system has 80 turns80\text{ turns} on its primary coil and 1200 turns1{}200\text{ turns} on its secondary coil. When the primary coil is energized by a 16 V AC16\text{ V AC} source, the secondary circuit delivers a current of 40 mA40\text{ mA} to its load. Assuming an ideal transformer, what is the current drawn by the primary coil?

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Cevap: 600 mA600\text{ mA}

Cevap

600 mA600\text{ mA}
In an ideal transformer, power is conserved (Pp=PsP_p = P_s), which means voltage and current vary inversely with the turns ratio. For this transformer, the secondary-to-primary turns ratio is 120080=15\frac{1{}200}{80} = 15. While voltage steps up by a factor of 15, current steps down by a factor of 15. Therefore, the primary current must be 15 times the secondary current: Ip=40 mA×15=600 mAI_p = 40\text{ mA} \times 15 = 600\text{ mA} (or 0.6 A0.6\text{ A}).

Adım Adım Çözüm

1
Calculate the turns ratio of the transformer
Turns ratio NsNp=120080=15\frac{N_s}{N_p} = \frac{1{}200}{80} = 15
The turns ratio establishes how voltage and current scale between the primary and secondary windings.
2
Apply the inverse current transformation formula for ideal transformers
Ip=Is×(NsNp)=40 mA×15=600 mAI_p = I_s \times \left(\frac{N_s}{N_p}\right) = 40\text{ mA} \times 15 = 600\text{ mA}
Because transformers conserve power (VpIp=VsIsV_p I_p = V_s I_s), a step-up in voltage results in a proportional step-down in current, meaning the primary current must be greater than the secondary current by the turns ratio.

Anahtar Kavram

Transformer Current and Turns Ratio Relationship
Tahmini Süre:1m 0s
Soru 965Soru →

An oscilloscope displays a periodic alternating voltage waveform on its screen. One complete cycle of the waveform occupies 4 horizontal divisions4\text{ horizontal divisions} across the graticule. If the oscilloscope's horizontal time base (Time/Div) control is set to 15 ms/div15\text{ ms/div}, what is the period of the waveform in milliseconds?

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Cevap: 60

Cevap

60 ms60\text{ ms}
The period (TT) of a signal displayed on an oscilloscope is found by multiplying the number of horizontal divisions for one complete cycle by the Time/Div control setting: 4 divisions×15 ms/div=60 ms4\text{ divisions} \times 15\text{ ms/div} = 60\text{ ms}.

Adım Adım Çözüm

1
Identify the number of horizontal graticule divisions occupied by one full waveform cycle.
4 divisions4\text{ divisions}
On an oscilloscope display, the horizontal axis represents time, and one full cycle corresponds to the period (TT).
2
Multiply the division count by the horizontal scale factor (15 ms/div15\text{ ms/div}).
4 div×15 ms/div=60 ms4\text{ div} \times 15\text{ ms/div} = 60\text{ ms}
Multiplying the span in divisions by the time allocated per division gives the total duration of one cycle.

Anahtar Kavram

Calculating waveform period from oscilloscope horizontal division settings
Tahmini Süre:45s
Soru 966Soru →

An electronics technician needs to verify the insulation integrity of high-voltage motor windings to ensure there is no current leakage to ground. Which specialized test instrument is designed specifically to measure these extremely high resistance values?

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Cevap: Megohmmeter

Cevap

Megohmmeter
A megohmmeter (commonly referred to as a megger) applies a high DC test voltage across an insulator or motor winding to measure resistance in the megohm range, making it the proper instrument for evaluating insulation integrity.

Adım Adım Çözüm

1
Identify the diagnostic requirement in the scenario.
The task requires measuring extremely high resistance values and checking insulation integrity against breakdown under high voltage.
Standard multimeters operate with low test voltages (3 to 9 V3\text{ to }9\text{ V}) and cannot expose insulation breakdown that occurs under high operational potentials.
2
Select the specialized test instrument designed for high-voltage resistance and insulation testing.
A megohmmeter (megger) applies a high DC test voltage (250 to 1000 V250\text{ to }1000\text{ V}) to measure resistance in the megohm or gigohm range.
The megohmmeter is specifically built for insulation testing and detecting minute leakage currents.

Anahtar Kavram

Specialized Testers - Megohmmeter (Megger) Insulation Testing
Tahmini Süre:45s
Soru 967Soru →

A portable electric heater is connected to a 120 V120\text{ V} direct-current power supply. If the heating element has an internal resistance of 24 Ω24\ \Omega, what is the current flowing through the circuit?

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Cevap: 5 A5\text{ A}

Cevap

5 A5\text{ A}
Using Ohm's Law (I=VRI = \frac{V}{R}), dividing the applied voltage of 120 V120\text{ V} by the resistance of 24 Ω24\ \Omega yields exactly 5 A5\text{ A}.

Adım Adım Çözüm

1
Identify the known values and state Ohm's Law formula for current.
Voltage V=120 VV = 120\text{ V}, Resistance R=24 ΩR = 24\ \Omega, Formula: I=VRI = \frac{V}{R}
Ohm's Law states that current is directly proportional to voltage and inversely proportional to resistance.
2
Substitute the circuit values into the formula and solve for current (II).
I=120 V24 Ω=5 AI = \frac{120\text{ V}}{24\ \Omega} = 5\text{ A}
Dividing 120120 by 2424 computes the magnitude of current flow in amperes.

Anahtar Kavram

Ohm's Law expresses the fundamental relationship among voltage, current, and resistance (I=V/RI = V / R).
Tahmini Süre:45s
Soru 968Soru →

A quartermaster is recording the number of uniform items issued per day over an 88-day period. The recorded numbers are 2424, 1919, 2828, 1717, 3333, 1616, 2020, and 2727. What is the median number of uniform items issued?

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Cevap: 22

Cevap

The median number of uniform items issued is 22.
The correct answer accurately sorts the dataset into numerical order (16,17,19,20,24,27,28,3316, 17, 19, 20, 24, 27, 28, 33) and calculates the average of the two middlemost numbers, 2020 and 2424, which results in 2222.

Adım Adım Çözüm

1
Sort the recorded numbers in ascending numerical order.
The sorted list is: 16,17,19,20,24,27,28,3316, 17, 19, 20, 24, 27, 28, 33.
The median is the middle value of an ordered dataset, so ordering is always the first step.
2
Identify the middle value(s).
Since there are 88 data points (an even number), there are two middle values: the 4th and 5th numbers, which are 2020 and 2424.
An even number of data points does not have a single exact middle number.
3
Calculate the average (mean) of the two middle values.
20+242=442=22\frac{20 + 24}{2} = \frac{44}{2} = 22
The median for an even number of data points is found by taking the mean of the two middlemost values.

Anahtar Kavram

To find the median of a dataset with an even number of values, the data must first be ordered from least to greatest, and then the mean of the two central values must be calculated.
Soru 969Soru →

In a solid copper conductor connected to a direct-current (DC) power source, the physical drift velocity of individual conduction electrons through the wire occurs at nearly the speed of light.

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Cevap: False

Cevap

False
The statement is false because free electrons in a metallic conductor undergo frequent collisions with copper atoms, resulting in a net drift velocity of only fractions of a millimeter per second, even though the electrical impulse travels across the circuit near the speed of light.

Adım Adım Çözüm

1
Differentiate between the speed of electric field propagation and the drift velocity of charge carriers.
The electric field sets up almost instantaneously across the conductor at near light speed, while charge carriers collide repeatedly with lattice atoms.
Understanding the physical mechanism of electrical current requires separating the transmission of electromagnetic energy from the physical motion of electrons.
2
Evaluate the actual physical movement rate of electrons in typical DC conductor currents.
Free electrons undergo constant random thermal collisions, resulting in a net directional drift velocity of only fractions of a millimeter to a few millimeters per second.
Frequent scattering against stationary copper ions severely impedes direct linear acceleration of individual electrons.
3
Determine the validity of the statement based on the evaluated speeds.
The statement claiming that electron drift velocity occurs at nearly the speed of light is false.
The statement falsely equates signal propagation speed with individual particle drift speed.

Anahtar Kavram

Distinction between electron drift velocity and electric field propagation speed in electrical current
Tahmini Süre:45s
Soru 970Soru →

A multi-component series circuit has failed and is drawing zero current due to an open fault. Arrange the following troubleshooting steps in the correct chronological sequence to safely and logically locate the open component using a digital multimeter (DMM) while the circuit is energized.

Öğeleri doğru sıraya koymak için sürükleyin

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Cevap

The correct sequence is to first verify the source voltage, anchor the negative reference lead, systematically probe downstream with the positive lead, observe the full source voltage across intact paths, and pinpoint the fault where the voltage abruptly drops to zero.
The voltage drop method is the most effective and professional way to locate an open fault in an energized circuit. In an open circuit, current cannot flow. According to Ohm's Law (V=I×RV = I \times R), if current (II) is zero, the voltage drop across any intact resistor is zero. Therefore, measuring anywhere between the positive terminal and the open fault will yield the full source voltage. Measuring anywhere after the open fault will yield zero volts because that section is physically isolated from the positive terminal but electrically connected to the negative reference. The steps outlined provide the logical, chronological, and safe procedure to trace this voltage path and isolate the break.

Adım Adım Çözüm

1
Understand the electrical behavior of an open circuit.
Current is 0 Amps, meaning intact resistors will have a voltage drop of 0 Volts (V=0×R=0V = 0 \times R = 0).
This principle dictates that the full source voltage will be measurable all the way up to the break.
2
Verify the baseline power supply.
The source voltage is confirmed to be present at the main terminals.
Troubleshooting downstream is useless if the main power source is dead or the battery is disconnected.
3
Establish a consistent measurement reference.
The black lead is fixed to ground, ensuring all readings are relative to 0 Volts.
Moving both leads simultaneously can cause confusion; anchoring one lead provides a steady reference point.
4
Trace the voltage potential through the circuit.
The meter reads full source voltage at each test point prior to the open fault.
The circuit wiring is intact up to the fault, extending the positive potential forward.
5
Identify the point of failure.
The fault is located exactly between the last point reading full voltage and the first point reading zero volts.
The open break physically separates the positive potential from the remainder of the circuit, causing the downstream voltage reading to drop to zero relative to ground.

Anahtar Kavram

Voltage Drop Troubleshooting Method
Tahmini Süre:1m 30s
Soru 971Soru →

Match each electronic component or resistor specification on the left with its correct circuit function or definition on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Potentiometer
Rheostat
Fixed Resistor
Tolerance Band

Eşleşmeler

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Cevap

Potentiometer matches with the three-terminal variable resistor used as an adjustable voltage divider; Rheostat matches with the two-terminal variable resistor used to adjust current flow; Fixed Resistor matches with the component providing a single, constant resistance value; Tolerance Band matches with the color-coded marking indicating allowable percentage variation from nominal resistance.
Each item is correctly matched to its standard electrical engineering and ASVAB definition: potentiometers provide variable three-terminal voltage division, rheostats provide two-terminal variable current control, fixed resistors supply a steady ohmic value, and tolerance bands indicate the precision percentage.

Adım Adım Çözüm

1
Identify the distinction between the two variable resistor types based on terminal count and primary function.
A potentiometer has 3 terminals and functions as a voltage divider; a rheostat has 2 active terminals in series to regulate current.
Variable resistors differ in wiring configuration: voltage division requires three connections across a potential difference, whereas current regulation requires two inline connections.
2
Identify the definition of a fixed resistor.
A fixed resistor provides a constant, unchangeable ohmic value.
Unlike potentiometers or rheostats, fixed resistors have no moving wiper mechanism.
3
Identify the purpose of the resistor tolerance band.
The tolerance band gives the allowable percentage deviation from the nominal value.
Manufacturing variations mean actual resistance lies within a percentage range defined by the 4th band.

Anahtar Kavram

Classification, terminal configurations, and functional specifications of fixed and variable resistors.
Tahmini Süre:40s
Soru 972Soru →

When trimming excess component leads on a printed circuit board after soldering through-hole parts, standard beveled cutting pliers pinch the wire and transmit mechanical shock into the solder joint, potentially fracturing the pad. Which specialized electrical hand tool features cutting edges that meet flat on the reverse side to produce a clean, flat cut without placing stress on the solder connection?

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Cevap: Flush cutters

Cevap

Flush cutters
Flush cutters are engineered specifically for electronics fabrication with single-beveled or shear-action blades that are perfectly flat on the back side. When placed against a circuit board, they slice through copper component leads cleanly without the crushing action that transfers damaging kinetic shock into the solder fillet.

Adım Adım Çözüm

1
Analyze the mechanical requirements of the task
Identified the need to trim component leads close to a circuit board without transmitting cutting shock to fragile solder pads.
Standard double-bevel cutting edges squeeze metal inward from both sides before severing it, creating an axial shockwave along the lead into the joint.
2
Evaluate the jaw geometry of electrical cutting hand tools
Flush cutters feature a zero-bevel flat outer face that shears through copper leads with a slicing action rather than a pinching action.
The flat back of flush cutters rests parallel to the board surface and produces a smooth cut with minimal residual mechanical strain.
3
Select the appropriate hand tool for delicate electronics work
Flush cutters are the designated tool for post-soldering lead trimming on printed circuit boards.
Other pliers either possess heavy double-beveled jaws or are specialized for insulation removal rather than lead trimming.

Anahtar Kavram

Hand tool cutting blade geometry and application in electronics assembly
Tahmini Süre:1m 15s
Soru 973Soru →

An aircraft avionics system is powered by a 28 V28\text{ V} DC supply connected in series with three components: a 40 Ω40\ \Omega indicator lamp, a 70 Ω70\ \Omega current-limiting resistor, and a 30 Ω30\ \Omega monitoring resistor. What is the voltage drop across the 70 Ω70\ \Omega current-limiting resistor?

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Cevap: 14 V14\text{ V}

Cevap

14 V14\text{ V}
The correct answer is 14 V14\text{ V}. In a series circuit, total resistance equals the sum of the individual resistors: 40 Ω+70 Ω+30 Ω=140 Ω40\ \Omega + 70\ \Omega + 30\ \Omega = 140\ \Omega. The circuit current is I=28 V/140 Ω=0.2 AI = 28\text{ V} / 140\ \Omega = 0.2\text{ A}. Multiplying this current by the 70 Ω70\ \Omega resistance gives a voltage drop of 0.2 A×70 Ω=14 V0.2\text{ A} \times 70\ \Omega = 14\text{ V}.

Adım Adım Çözüm

1
Calculate the total equivalent resistance (RtotalR_{\text{total}}) of the series circuit.
Rtotal=40 Ω+70 Ω+30 Ω=140 ΩR_{\text{total}} = 40\ \Omega + 70\ \Omega + 30\ \Omega = 140\ \Omega
In a series circuit, total resistance is the algebraic sum of all individual resistances.
2
Determine the common circuit current (II) using Ohm's Law.
I=VtotalRtotal=28 V140 Ω=0.2 AI = \frac{V_{\text{total}}}{R_{\text{total}}} = \frac{28\text{ V}}{140\ \Omega} = 0.2\text{ A}
Current remains constant through every component along a single series path.
3
Calculate the voltage drop across the 70 Ω70\ \Omega resistor (V70ΩV_{70\Omega}).
V70Ω=I×R=0.2 A×70 Ω=14 VV_{70\Omega} = I \times R = 0.2\text{ A} \times 70\ \Omega = 14\text{ V}
Applying Ohm's Law (V=I×RV = I \times R) to the specific component yields its proportional voltage drop.

Anahtar Kavram

Series Circuit Resistance and Voltage Division

Alternatif Yöntem

Use the voltage divider formula directly: V70Ω=28 V×(70 Ω40 Ω+70 Ω+30 Ω)=28 V×70140=28 V×0.5=14 VV_{70\Omega} = 28\text{ V} \times \left(\frac{70\ \Omega}{40\ \Omega + 70\ \Omega + 30\ \Omega}\right) = 28\text{ V} \times \frac{70}{140} = 28\text{ V} \times 0.5 = 14\text{ V}.
Tahmini Süre:1m 0s
Soru 974Soru →

An automotive technician tests an unpowered single-pole single-throw (SPST) toggle switch that has been removed from a vehicle's dashboard. With the digital multimeter set to the resistance (Ω\Omega) mode and the switch set to the OFF position, what should the meter display across the switch terminals if the switch is functioning normally?

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Cevap: An infinite resistance or "OL" (overload) reading, indicating an open circuit

Cevap

An infinite resistance or "OL" (overload) reading, indicating an open circuit
When an SPST toggle switch is placed in the OFF position, its internal mechanical contacts are physically separated. This creates an open circuit with infinite electrical resistance. A digital multimeter set to resistance (Ω\Omega) or continuity mode will display this condition as "OL" (overload / open loop) or infinite resistance (∞\infty), confirming that no current can flow across the open terminals.

Adım Adım Çözüm

1
Identify the physical state of the switch contacts in the OFF position
The internal mechanical contacts are physically separated (open)
An SPST switch in the OFF position interrupts the current path by creating an air gap between terminals.
2
Determine how a digital multimeter interprets an open path in resistance (Ω\Omega) mode
The meter measures infinite resistance, displayed as "OL" or "∞\infty"
An open circuit provides no path for the multimeter's internal sensing current to return.

Anahtar Kavram

Interpreting open circuit resistance readings on a digital multimeter
Tahmini Süre:1m 0s
Soru 975Soru →

An electronics technician is designing a control panel that uses a single DC supply line to illuminate either a green 'Standby' lamp or a red 'Run' lamp, ensuring that only one lamp can receive power at any given time. Which type of switch configuration is required to route power between these two alternate loads?

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Cevap: Single-pole, double-throw (SPDT) switch

Cevap

Single-pole, double-throw (SPDT) switch
A single-pole, double-throw (SPDT) switch consists of a single common movable contact (one pole) that can connect to either of two stationary output contacts (two throws). Moving the switch actuator connects the single supply line to either the Standby lamp or the Run lamp, preventing both from being energized simultaneously.

Adım Adım Çözüm

1
Identify the number of input circuits (poles) required by the scenario.
One incoming DC supply line means 1 pole (Single-Pole, SP).
The 'pole' count defines how many independent input circuits or movable contact arms are operated by the switch mechanism.
2
Identify the number of output positions (throws) needed for switching between loads.
Two distinct output paths (Standby lamp and Run lamp) means 2 throws (Double-Throw, DT).
The 'throw' count defines how many individual output positions or contacts each pole can connect to.
3
Combine pole and throw nomenclature to select the appropriate component.
Single-Pole, Double-Throw (SPDT).
An SPDT switch directs current from one common terminal to either of two branch terminals in a mutually exclusive manner.

Anahtar Kavram

Switch pole and throw configurations (SPST, SPDT, DPST, DPDT)
Tahmini Süre:1m 0s
Soru 976Soru →

In a standard electronic schematic diagram, what does the triangular arrowhead of a semiconductor diode symbol indicate?

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Cevap: The permitted direction of conventional current flow

Cevap

The permitted direction of conventional current flow
In standard electronic schematic symbols, the triangular arrowhead points from the anode toward the cathode, designating the direction that conventional electric current (from positive to negative) is allowed to flow during forward bias.

Adım Adım Çözüm

1
Analyze the anatomy of a standard semiconductor diode schematic symbol.
The symbol features a triangle pointing directly toward a vertical barrier line.
Recognizing the individual elements of schematic drafting symbols is necessary to read circuit diagrams.
2
Correlate the triangular symbol element with electrical flow conventions.
The triangle represents an arrowhead pointing from the anode (positive terminal) to the cathode (negative terminal), matching conventional current direction.
Standard electronics schematics use conventional current (positive-to-negative flow) to define component polarity arrows.

Anahtar Kavram

A semiconductor diode schematic symbol uses a triangular arrowhead pointing from anode to cathode to indicate the permitted direction of conventional current flow.
Tahmini Süre:45s
Soru 977Soru →

An industrial control panel is powered by a 36 V36\text{ V} DC source. The main circuit splits into three parallel branches. Branch one powers a cooling unit that dissipates 108 W108\text{ W} of power. Branch two contains an 18 Ω18\ \Omega limiting resistor. Branch three contains a sensor module with an unknown resistance. If a technician measures the total equivalent resistance of this entire parallel network to be exactly 4 Ω4\ \Omega, what is the resistance of the sensor module?

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Cevap: 9 Ω9\ \Omega

Cevap

The resistance of the sensor module in the third branch is 9 Ω9\ \Omega.
To find the resistance of a single parallel branch, you need the voltage across it and the current through it. The voltage is the source voltage (36 V36\text{ V}). The total current is 9 A9\text{ A} (36 V/4 Ω36\text{ V} / 4\ \Omega). Subtracting the current from the first branch (108 W/36 V=3 A108\text{ W} / 36\text{ V} = 3\text{ A}) and the second branch (36 V/18 Ω=2 A36\text{ V} / 18\ \Omega = 2\text{ A}) leaves 4 A4\text{ A} flowing through the third branch. Using Ohm's Law (R=V/IR = V/I), 36 V/4 A36\text{ V} / 4\text{ A} equals 9 Ω9\ \Omega.

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1
Calculate the total current (ItotalI_{total}) drawn by the entire circuit.
Itotal=VRtotal=36 V4 Ω=9 AI_{total} = \frac{V}{R_{total}} = \frac{36\text{ V}}{4\ \Omega} = 9\text{ A}
Ohm's law applies to the circuit as a whole just as it does to individual components.
2
Calculate the current flowing through Branch 1 (I1I_1).
I1=P1V=108 W36 V=3 AI_1 = \frac{P_1}{V} = \frac{108\text{ W}}{36\text{ V}} = 3\text{ A}
In a parallel circuit, the voltage across each branch is equal to the source voltage. We use the power formula (P=V×IP = V \times I) rearranged to solve for current.
3
Calculate the current flowing through Branch 2 (I2I_2).
I2=VR2=36 V18 Ω=2 AI_2 = \frac{V}{R_2} = \frac{36\text{ V}}{18\ \Omega} = 2\text{ A}
Using Ohm's law (I=V/RI = V/R) with the known voltage and resistance for this specific branch.
4
Determine the current flowing through the unknown Branch 3 (I3I_3).
I3=Itotal−(I1+I2)=9 A−(3 A+2 A)=4 AI_3 = I_{total} - (I_1 + I_2) = 9\text{ A} - (3\text{ A} + 2\text{ A}) = 4\text{ A}
Kirchhoff's Current Law states that the total current entering a parallel network must equal the sum of the currents in individual branches.
5
Calculate the resistance of Branch 3 (R3R_3).
R3=VI3=36 V4 A=9 ΩR_3 = \frac{V}{I_3} = \frac{36\text{ V}}{4\text{ A}} = 9\ \Omega
Applying Ohm's law once more to the specific values of the third branch.

Anahtar Kavram

Parallel Circuit Current and Power Laws
Soru 978Soru →

Match each electrical material to its correct classification and physical property.

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Öğeler

Silver
Silicon
Rubber
Ceramic

Eşleşmeler

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Cevap

Silver matches with the conductor having high free electron concentration; Silicon matches with the semiconductor having four valence electrons; Rubber matches with the flexible insulator; Ceramic matches with the rigid, heat-resistant insulator.
Materials are classified by their atomic structure and ability to carry electrical current. Silver contains loosely bound electrons making it an excellent conductor; Silicon contains four valence electrons making it a semiconductor; Rubber has tightly bound electrons making it a flexible insulator; Ceramic has tightly bound ionic and covalent bonds making it a rigid, heat-resistant insulator.

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1
Identify the conductor among the listed materials.
Silver is a metal with a high density of free valence electrons, allowing electrical current to pass with minimal resistance.
Conductors readily allow electron flow due to loosely bound valence electrons.
2
Identify the semiconductor among the listed materials.
Silicon contains four valence electrons, giving it an intermediate conductivity level between conductors and insulators.
Group IV elements like silicon and germanium serve as the foundational materials for solid-state electronics.
3
Distinguish between the two insulating materials by their mechanical and thermal properties.
Rubber is a flexible insulator commonly used on cables, while ceramic is a rigid, heat-resistant insulator used in high-voltage applications.
Both materials possess tightly bound electrons that resist current flow, but serve distinct structural applications.

Anahtar Kavram

Classification of materials into conductors, semiconductors, and insulators based on electron mobility and atomic structure
Tahmini Süre:45s
Soru 979Soru →

A four-band carbon-film resistor has the color bands in the following sequence: Blue, Gray, Brown, and Gold. What is the nominal resistance value and tolerance rating of this resistor?

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Cevap: 680 Ω with ±5% tolerance680\ \Omega\text{ with } \pm 5\%\text{ tolerance}

Cevap

680 Ω with ±5% tolerance680\ \Omega\text{ with } \pm 5\%\text{ tolerance}
Decoding the four color bands in order yields: first band (Blue) = 6, second band (Gray) = 8, third band (Brown) = ×101\times 10^1 (1010), and fourth band (Gold) = ±5%\pm 5\%. Calculating 68×1068 \times 10 gives a nominal resistance of 680 Ω680\ \Omega with ±5%\pm 5\% tolerance.

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1
Identify the significant digits from the first two color bands
Blue corresponds to the digit 6 and Gray corresponds to the digit 8, forming the significant number 68.
In a standard four-band resistor, the first two bands represent the first and second significant digits of the resistance value.
2
Determine the multiplier from the third color band and calculate the nominal resistance
Brown corresponds to a multiplier of 10110^1 (1010). Multiplying 68×10=680 Ω68 \times 10 = 680\ \Omega.
The third band indicates the power of ten by which the significant digits are multiplied.
3
Identify the tolerance percentage from the fourth color band
Gold corresponds to a tolerance of ±5%\pm 5\%.
The fourth band indicates the manufacturing tolerance of the resistor.

Anahtar Kavram

Four-band resistor color code decoding
Tahmini Süre:35s
Soru 980Soru →

A heating resistor with a resistance of 20 \Omega20\text{ \Omega} has a steady current of 3 A3\text{ A} flowing through it. What is the total electrical power dissipated by the resistor?

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Cevap: 180 W180\text{ W}

Cevap

180 W180\text{ W}
Electrical power dissipated by a resistor when current and resistance are known is determined by the formula P=I2×RP = I^2 \times R. Substituting the given values gives P=(3 A)2×20 \Omega=9×20=180 WP = (3\text{ A})^2 \times 20\text{ \Omega} = 9 \times 20 = 180\text{ W}.

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1
Identify the known circuit parameters and the appropriate power formula.
Known values: I=3 AI = 3\text{ A}, R=20 \OmegaR = 20\text{ \Omega}. Applicable formula: P=I2×RP = I^2 \times R.
When current and resistance are known, Watt's law in the form P=I2RP = I^2 R gives electrical power directly.
2
Square the current value.
I2=(3 A)2=9 A2I^2 = (3\text{ A})^2 = 9\text{ A}^2.
Power dissipation is proportional to the square of the current flowing through a resistor.
3
Multiply the squared current by the resistance.
P=9×20=180 WP = 9 \times 20 = 180\text{ W}.
Multiplying squared current by resistance yields total dissipated power in watts.

Anahtar Kavram

Electrical power dissipation in a resistive component using Joule's/Watt's law (P=I2RP = I^2 R).
Tahmini Süre:45s
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