Electronic Components

211 soru

Soru 61Soru →

While standard bipolar junction transistors (BJTs) operate as current-controlled components, field-effect transistors (FETs) are commonly used in high-impedance input stages. What is the primary operating mechanism of a field-effect transistor?

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Cevap: Regulating current between the source and drain using an electric field established by a gate voltage

Cevap

Regulating current between the source and drain using an electric field established by a gate voltage
A field-effect transistor (FET) controls the flow of electrical charge carriers between the source and drain terminals by varying the strength of an electrostatic field within the semiconductor channel. This field is established by applying a voltage to the gate terminal, allowing the device to modulate conductivity with almost zero input gate current.

Adım Adım Çözüm

1
Identify the fundamental category and terminals of a Field-Effect Transistor (FET)
FETs have three primary terminals: Gate, Drain, and Source.
Recognizing terminal designations separates FET functionality from BJT terminals (Base, Collector, Emitter).
2
Determine the control mechanism of a FET
An electric field created by voltage applied to the gate controls the conductive channel between the source and drain.
FETs are voltage-controlled solid-state devices that draw negligible gate current due to extremely high input resistance.

Anahtar Kavram

Field-Effect Transistor (FET) Voltage-Controlled Operation
Tahmini Süre:1m 0s
Soru 62Soru →

An automotive audio technician installs two filter capacitors connected in parallel across a power line to suppress voltage ripple. If the individual capacitor values are 47 μF47\text{ }\mu\text{F} and 33 μF33\text{ }\mu\text{F}, what is the total equivalent capacitance of this parallel combination in microfarads (μF\mu\text{F})?

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Cevap: 80

Cevap

80 microfarads (80 μF80\text{ }\mu\text{F})
When capacitors are wired in parallel, the total plate area increases, allowing more charge to be stored at a given voltage. Therefore, the equivalent capacitance is the simple arithmetic sum of the individual capacitances: 47 μF+33 μF=80 μF47\text{ }\mu\text{F} + 33\text{ }\mu\text{F} = 80\text{ }\mu\text{F}.

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1
Identify the network connection type and select the appropriate rule.
Capacitors are connected in parallel.
Connecting capacitors in parallel increases the total effective plate area, so their capacitances add directly.
2
Calculate the total capacitance using the sum formula Ctotal=C1+C2C_{\text{total}} = C_1 + C_2.
Ctotal=47 μF+33 μF=80 μFC_{\text{total}} = 47\text{ }\mu\text{F} + 33\text{ }\mu\text{F} = 80\text{ }\mu\text{F}
Direct addition of the individual capacitance ratings yields the total circuit capacitance.

Anahtar Kavram

Parallel Capacitance Calculation
Tahmini Süre:45s
Soru 63Soru →

A Single-Pole, Single-Throw (SPST) switch is capable of opening and closing two separate, electrically isolated circuits simultaneously.

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Cevap: False

Cevap

False. A Single-Pole, Single-Throw (SPST) switch controls only one individual circuit.
The statement is false because the pole count specifies how many distinct circuits a switch controls. A Single-Pole (SP) switch controls exactly one circuit path. Operating two separate, electrically isolated circuits simultaneously requires a Double-Pole (DP) switch, such as a DPST switch.

Adım Adım Çözüm

1
Define the meaning of 'pole' in switch terminology.
The number of poles indicates how many separate, isolated electrical circuits the switch can control at one time.
Understanding switch nomenclature requires distinguishing between poles (circuits controlled) and throws (contact positions per pole).
2
Evaluate the capability of a Single-Pole (SP) switch against the statement.
A single-pole switch has only one set of contacts and can only control a single circuit.
To simultaneously switch two independent circuits, a double-pole (DP) configuration with a shared mechanical actuator is required.

Anahtar Kavram

Switch Poles and Throws Nomenclature
Tahmini Süre:30s
Soru 64Soru →

An automotive direct-current (DC) blower motor circuit with a continuous operating current of 5 A5\text{ A} experiences a brief transient inrush current of 18 A18\text{ A} for 150 ms150\text{ ms} each time the motor starts. When a technician installs a standard 6 A6\text{ A} fast-acting fuse, the fuse opens immediately upon starting the motor despite no short circuit or wiring fault being present. To resolve this nuisance tripping while still providing reliable overcurrent and thermal protection for the continuous load and wiring, which protective device should be installed?

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Cevap: A 6 A6\text{ A} slow-blow (time-delay) fuse connected in series with the motor feed conductor

Cevap

A 6 A6\text{ A} slow-blow (time-delay) fuse connected in series with the motor feed conductor
Inductive loads such as electric motors draw high transient inrush currents upon startup before counter-electromotive force (CEMF) develops. A slow-blow (time-delay) fuse utilizes a dual-element or thermal lag construction designed specifically to pass short-duration overcurrent surges without melting, while still opening quickly under prolonged overloads or dead short circuits. Sizing the slow-blow fuse at 6 A6\text{ A} and placing it in series provides full circuit protection matched to the 5 A5\text{ A} running current without nuisance tripping.

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1
Analyze the load characteristics and failure mode
The DC motor requires 5 A5\text{ A} continuous running current but produces a temporary inductive inrush surge of 18 A18\text{ A} (3.6×3.6\times rated current) lasting 150 ms150\text{ ms}. Fast-acting fuses react instantaneously to current spikes, causing nuisance blowing during normal motor starts.
Inductive and capacitive loads naturally draw transient inrush currents that must be accommodated without blowing the protective element under non-fault conditions.
2
Determine the appropriate fuse operating characteristic and rating
A slow-blow (time-delay) fuse rated at 6 A6\text{ A} contains a dual-element or spring-loaded thermal design that absorbs brief transient current spikes without melting, yet reliably opens if current exceeds 6 A6\text{ A} continuously.
Maintaining the current rating near the continuous operating load (6 A6\text{ A} for a 5 A5\text{ A} circuit) ensures proper thermal overload protection for the wiring and motor windings.
3
Verify proper circuit topology for overcurrent protection
The protective device must be placed in series with the ungrounded supply conductor so that opening the fuse disconnects the entire current path to the load.
Series placement ensures the total circuit current passes through the protective device.

Anahtar Kavram

Selection and application of time-delay (slow-blow) fuses for inductive inrush loads
Tahmini Süre:1m 15s
Soru 65Soru →

In an electronic filter circuit, two inductors with values L1=30 mHL_1 = 30\text{ mH} and L2=20 mHL_2 = 20\text{ mH} are connected in parallel. This parallel pair is connected in series with a third inductor L3=18 mHL_3 = 18\text{ mH} and a fourth inductor L4=10 mHL_4 = 10\text{ mH}. Assuming negligible mutual inductance between the coils, what is the total equivalent inductance of the circuit in millihenries (mH\text{mH})?

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Cevap: 40

Cevap

40 mH
The total inductance is 40 mH40\text{ mH}. Inductors follow the same combination rules as resistors: the parallel pair (30 mH30\text{ mH} and 20 mH20\text{ mH}) yields an equivalent inductance of 12 mH12\text{ mH}, which when added to the series inductors (18 mH18\text{ mH} and 10 mH10\text{ mH}) gives 12+18+10=40 mH12 + 18 + 10 = 40\text{ mH}.

Adım Adım Çözüm

1
Calculate the equivalent inductance of the two parallel inductors L1L_1 and L2L_2.
Lp=L1×L2L1+L2=30 mH×20 mH30 mH+20 mH=60050=12 mHL_p = \frac{L_1 \times L_2}{L_1 + L_2} = \frac{30\text{ mH} \times 20\text{ mH}}{30\text{ mH} + 20\text{ mH}} = \frac{600}{50} = 12\text{ mH}
Inductors in parallel combine using reciprocal addition, identically to resistors in parallel.
2
Calculate the total circuit inductance by summing the parallel combination with the remaining series inductors L3L_3 and L4L_4.
Ltotal=Lp+L3+L4=12 mH+18 mH+10 mH=40 mHL_{total} = L_p + L_3 + L_4 = 12\text{ mH} + 18\text{ mH} + 10\text{ mH} = 40\text{ mH}
Inductors in series combine via direct addition because the magnetic fields and induced voltages add along the common current path.

Anahtar Kavram

Inductors combine like resistors: series inductances add directly, while parallel inductances combine using reciprocal addition.
Tahmini Süre:1m 30s
Soru 66Soru →

An audio technician connects a capacitor in series with a high-frequency speaker (tweeter) inside a multi-speaker enclosure. What is the primary electrical reason for using a capacitor in this configuration?

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Cevap: It easily passes high-frequency signals due to lower capacitive reactance while blocking low frequencies.

Cevap

The capacitor is used because it easily passes high-frequency signals due to lower capacitive reactance while blocking low frequencies.
Capacitive reactance (XC=12πfCX_C = \frac{1}{2\pi f C}) is inversely proportional to the frequency of the electrical signal. For high-frequency signals directed to a tweeter, the capacitor offers very low opposition (low reactance), allowing the high-frequency audio to pass smoothly. At low frequencies or DC, the reactance becomes extremely high, blocking low-frequency bass currents that could overheat or damage the delicate tweeter voice coil.

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1
Analyze the relationship between frequency and capacitive reactance (XCX_C).
Capacitive reactance is inversely proportional to frequency, governed by the formula XC=12πfCX_C = \frac{1}{2\pi f C}.
Understanding how reactance changes with frequency is essential for determining how AC audio signals behave across the component.
2
Determine the effect on high versus low audio frequencies.
At high frequencies (treble), XCX_C is very low, presenting minimal opposition to current; at low frequencies (bass) and DC (f=0f = 0), XCX_C becomes extremely large, effectively blocking the signal.
Tweeters are designed to handle only high-frequency signals, so placing a capacitor in series forms a high-pass filter that protects the tweeter from damaging low frequencies.

Anahtar Kavram

Capacitors exhibit capacitive reactance inversely proportional to frequency, acting as high-pass filters in series audio crossover circuits.
Tahmini Süre:1m 0s
Soru 67Soru →

In advanced circuit protection, different devices are engineered to respond to specific types of faults using unique physical properties. Based on their operating principles, match each specialized electronic protective device to its precise operational mechanism.

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Öğeler

Magnetic Circuit Breaker
Thermal Circuit Breaker
Slow-Blow (Time-Delay) Fuse
Metal Oxide Varistor (MOV)
Crowbar Circuit

Eşleşmeler

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Cevap

Magnetic Circuit Breaker matches the electromagnetic coil mechanism. Thermal Circuit Breaker matches the bimetallic strip mechanism. Slow-Blow Fuse matches the inrush current dual-element design. MOV matches the impedance-dropping clamping mechanism. Crowbar Circuit matches the deliberate shorting mechanism.
Each protective component relies on a distinct physical property: electromagnetism for magnetic breakers, thermodynamics for thermal breakers, thermal inertia for slow-blow fuses, non-linear resistance for MOVs, and intentional fault-creation for crowbar circuits.

Adım Adım Çözüm

1
Analyze devices designed for overcurrent protection versus overvoltage protection.
Magnetic breakers, thermal breakers, and slow-blow fuses handle overcurrent. MOVs and crowbar circuits handle overvoltage.
Separating the components by their primary fault protection type narrows down the possible operating mechanisms.
2
Differentiate between the overcurrent devices based on their physical triggers.
Thermal breakers use heat (bimetallic strip). Magnetic breakers use electromagnetism (coils). Slow-blow fuses use dual-elements to delay blowing during temporary inrush currents.
Each overcurrent device is selected based on load characteristics (e.g., motors need slow-blow; precise instant tripping needs magnetic).
3
Differentiate between the overvoltage devices based on how they clear the fault.
MOVs passively clamp voltage by changing their internal resistance. Crowbar circuits actively short the circuit to force a fuse to blow.
Understanding the difference between passive clamping (varistors) and active destructive diversion (crowbar) confirms the final two matches.

Anahtar Kavram

Advanced circuit protection mechanisms (Overcurrent vs. Overvoltage strategies)
Soru 68Soru →

For a bipolar junction transistor (BJT) to operate in the active amplification mode, the base-emitter junction must be forward-biased while the base-collector junction is reverse-biased.

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Cevap: True

Cevap

True. Operating a bipolar junction transistor in the active amplification region requires a forward-biased base-emitter junction and a reverse-biased base-collector junction.
The statement is correct because linear amplification in a bipolar junction transistor strictly requires the input base-emitter diode junction to be forward-biased to initiate current flow, and the output collector-base junction to be reverse-biased to sweep and gather charge carriers into the collector circuit.

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1
Identify the specified operating state of the transistor
The transistor is designated to operate in active (linear) amplification mode.
A transistor exhibits distinct junction biasing configurations depending on whether it functions in cutoff, saturation, or active mode.
2
Determine the required bias across the base-emitter junction
The base-emitter junction must be forward-biased.
Forward-biasing this junction overcomes the internal barrier potential (approximately 0.7 V for silicon) and injects carriers into the base.
3
Determine the required bias across the base-collector junction
The base-collector junction must be reverse-biased.
Reverse-biasing this junction establishes a wide depletion region with an electric field that sweeps the injected carriers into the collector.
4
Evaluate the accuracy of the statement
The statement correctly describes both required junction conditions.
The combination of a forward-biased base-emitter junction and a reverse-biased base-collector junction precisely defines active region operation.

Anahtar Kavram

Bipolar Junction Transistor Biasing and Operating Modes
Tahmini Süre:45s
Soru 69Soru →

Which of the following statements correctly identifies the primary function and operating principle of a capacitor in an electronic circuit?

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Cevap: It stores electrical energy in an electrostatic field and opposes sudden changes in voltage.

Cevap

It stores electrical energy in an electrostatic field and opposes sudden changes in voltage.
A capacitor is designed with two conductive plates separated by an insulating dielectric material. When a voltage is applied, opposite charges accumulate on the plates, establishing an electrostatic field that stores electrical energy. Because charge accumulation requires finite time, a capacitor naturally opposes any sudden change in voltage across its terminals.

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1
Identify the fundamental physical construction and energy storage mechanism of a capacitor.
A capacitor consists of two conducting plates separated by an insulating dielectric, which accumulates opposite charges to establish an electrostatic field.
Capacitors store potential electrical energy in an electrostatic field rather than a magnetic field.
2
Determine how a capacitor interacts with circuit voltage and current over time.
Because electrical charge requires finite time to build up or dissipate across the plates (q=C⋅Vq = C \cdot V), the component naturally resists instantaneous changes in voltage.
This property makes capacitors essential for filtering voltage ripples in power supplies and setting time constants in electronic circuits.

Anahtar Kavram

Capacitor Energy Storage and Voltage Regulation
Tahmini Süre:45s
Soru 70Soru →

An automotive starter circuit uses an electromechanical relay between the ignition switch and the starter motor. What is the primary purpose of using a relay in this circuit?

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Cevap: To allow a low-current switch on the dashboard to safely control the high-current starter motor

Cevap

Allowing a low-current switch on the dashboard to safely control the high-current starter motor
An electromechanical relay uses a small control current flowing through an electromagnet coil to close heavy-duty contacts. In an automotive starting system, this enables a driver to use a small, safe ignition switch to engage the hundreds of amperes demanded by the starter motor without running heavy cables through the passenger cabin.

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1
Identify the basic operating principle of an electromechanical relay
A small control current through a wire coil generates a magnetic field that moves an armature to open or close heavy-duty load contacts.
Relays provide electrical isolation and current amplification between the control circuit and the load circuit.
2
Apply the relay function to the automotive starter scenario
The starter motor requires hundreds of amperes of current, which would overheat standard dashboard toggle switches and wiring if routed directly.
Placing the relay near the battery and starter allows short, heavy-gauge cables for the high-current path while using lightweight wiring for the ignition switch.

Anahtar Kavram

Electromechanical Relay Operation and High-Current Load Switching
Tahmini Süre:40s
Soru 71Soru →

Complete the statement describing the dual-action operating mechanisms inside a standard industrial circuit breaker.

Aşağıdaki boşlukları doldurun

In a thermal-magnetic circuit breaker, sustained moderate overloads cause a strip to heat and deflect over time, whereas severe short-circuit currents create an intense magnetic field in an coil to trip the mechanism instantaneously.
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Cevap

Blank 1: bimetallic (or bimetal); Blank 2: electromagnetic (or magnetic)
Thermal-magnetic circuit breakers provide coordinated protection using two distinct physical principles: a bimetallic strip that flexes under prolonged thermal stress to prevent wire insulation degradation, and an electromagnetic solenoid that provides virtually instantaneous tripping when massive fault currents occur.

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1
Identify the thermal overload component
Bimetallic strip
Prolonged overcurrent conditions produce resistive heat proportional to I2R⋅tI^2R \cdot t. Two bonded metals with different coefficients of thermal expansion expand at unequal rates, causing the strip to bend and unlatch the breaker contacts after a calibrated time delay.
2
Identify the short-circuit protection component
Electromagnetic coil (solenoid)
High-magnitude fault currents (such as direct phase-to-ground or phase-to-phase shorts) generate an immediate, powerful magnetic field inside a wire coil/solenoid, pulling an internal armature to trip the breaker instantly before conductors reach destructive temperatures.

Anahtar Kavram

Dual-trip circuit breakers utilize a slow-responding bimetallic element for thermal overcurrent protection and a rapid-responding electromagnetic solenoid for short-circuit protection.
Tahmini Süre:1m 15s
Soru 72Soru →

An industrial electronics technician is servicing a timing circuit on an automated assembly line. The circuit network contains two 12 μF12\text{ }\mu\text{F} capacitors connected in series, and this combination is connected in parallel with a third capacitor rated at 14 μF14\text{ }\mu\text{F}. What is the total equivalent capacitance of this circuit network in microfarads (μF\mu\text{F})?

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Cevap: 20

Cevap

20 μF20\text{ }\mu\text{F}
For the series branch, two identical 12 μF12\text{ }\mu\text{F} capacitors yield an equivalent capacitance of 6 μF6\text{ }\mu\text{F}. When placed in parallel with the 14 μF14\text{ }\mu\text{F} capacitor, the capacitances add directly (6 μF+14 μF6\text{ }\mu\text{F} + 14\text{ }\mu\text{F}), giving a total equivalent capacitance of 20 μF20\text{ }\mu\text{F}.

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1
Calculate the equivalent capacitance of the two 12 μF12\text{ }\mu\text{F} capacitors connected in series.
Cs=6 μFC_s = 6\text{ }\mu\text{F}
Capacitors in series combine reciprocally: 1Cs=1C1+1C2\frac{1}{C_s} = \frac{1}{C_1} + \frac{1}{C_2}, or Cs=Cn=122=6 μFC_s = \frac{C}{n} = \frac{12}{2} = 6\text{ }\mu\text{F}.
2
Add the capacitance of the parallel branch to the series equivalent.
Ctotal=20 μFC_{\text{total}} = 20\text{ }\mu\text{F}
Capacitors in parallel add directly together: Ctotal=Cs+C3=6 μF+14 μF=20 μFC_{\text{total}} = C_s + C_3 = 6\text{ }\mu\text{F} + 14\text{ }\mu\text{F} = 20\text{ }\mu\text{F}.

Anahtar Kavram

Series and parallel capacitor combinations and equivalent capacitance calculations
Tahmini Süre:1m 0s
Soru 73Soru →

A power adapter uses a step-down transformer with 400 turns400\text{ turns} on the primary coil and 20 turns20\text{ turns} on the secondary coil. If an input voltage of 120 V AC120\text{ V AC} is applied across the primary coil, what is the secondary output voltage in volts?

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Cevap: 6

Cevap

The secondary output voltage is 6 V6\text{ V}.
In a transformer, the ratio of secondary voltage to primary voltage equals the ratio of secondary turns to primary turns (Vs/Vp=Ns/NpV_s / V_p = N_s / N_p). With 400400 primary turns and 2020 secondary turns, the turns ratio is 20/400=1/2020 / 400 = 1/20. Multiplying the primary voltage (120 V120\text{ V}) by 1/201/20 yields a secondary output voltage of 6 V6\text{ V}.

Adım Adım Çözüm

1
Identify the given transformer parameters from the problem statement.
Vp=120 VV_p = 120\text{ V}, Np=400 turnsN_p = 400\text{ turns}, and Ns=20 turnsN_s = 20\text{ turns}.
These parameters are required to determine the relationship between primary and secondary voltages.
2
Set up the transformer turns ratio equation relating primary and secondary voltages to coil turns.
VsVp=NsNp\frac{V_s}{V_p} = \frac{N_s}{N_p}
The voltage induced across a transformer winding is directly proportional to the number of turns in that winding.
3
Substitute the known values into the equation and compute the secondary voltage VsV_s.
Vs=120 V×(20400)=120 V×0.05=6 VV_s = 120\text{ V} \times \left(\frac{20}{400}\right) = 120\text{ V} \times 0.05 = 6\text{ V}
Direct algebraic calculation yields the step-down output voltage.

Anahtar Kavram

Transformer Turns Ratio and Voltage Transformation
Tahmini Süre:45s
Soru 74Soru →

A step-up transformer in a specialized power supply is connected to a 120 V AC120\text{ V AC} source on its primary side. The secondary circuit delivers a current of 24 mA24\text{ mA} across a 25 kΩ25\text{ k}\Omega resistive load. If the primary winding has 150 turns150\text{ turns}, what is the total number of turns on the secondary winding?

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Cevap: 750 turns750\text{ turns}

Cevap

750 turns750\text{ turns}
The correct answer is 750 turns750\text{ turns}. First, determine the secondary voltage using Ohm's Law: Vs=Is×RL=(0.024 A)×(25000 Ω)=600 VV_s = I_s \times R_L = (0.024\text{ A}) \times (25{}000\,\Omega) = 600\text{ V}. Then, apply the transformer ratio formula NsNp=VsVp\frac{N_s}{N_p} = \frac{V_s}{V_p}, yielding Ns=150×(600120)=750 turnsN_s = 150 \times \left(\frac{600}{120}\right) = 750\text{ turns}.

Adım Adım Çözüm

1
Calculate the secondary voltage (VsV_s) across the load resistor using Ohm's Law (V=I×RV = I \times R).
Vs=(24 mA)×(25 kΩ)=(0.024 A)×(25000 Ω)=600 VV_s = (24\text{ mA}) \times (25\text{ k}\Omega) = (0.024\text{ A}) \times (25{}000\,\Omega) = 600\text{ V}
Determining the voltage across the secondary winding is necessary to establish the transformer's voltage transformation ratio.
2
Apply the transformer turns ratio equation that relates winding turns directly to voltage.
NsNp=VsVp\frac{N_s}{N_p} = \frac{V_s}{V_p}
In an ideal transformer, the ratio of secondary-to-primary turns is directly proportional to the ratio of secondary-to-primary voltage.
3
Substitute the known values (Vs=600 VV_s = 600\text{ V}, Vp=120 VV_p = 120\text{ V}, and Np=150 turnsN_p = 150\text{ turns}) to solve for the secondary turns (NsN_s).
Ns=150×(600 V120 V)=150×5=750 turnsN_s = 150 \times \left(\frac{600\text{ V}}{120\text{ V}}\right) = 150 \times 5 = 750\text{ turns}
Multiplying the primary turns by the voltage scaling factor gives the required secondary turns.

Anahtar Kavram

Transformer turns ratio and multi-step AC secondary load calculations
Tahmini Süre:2m 0s
Soru 75Soru →

In a bipolar junction transistor (BJT) amplifier circuit operating in its active region, a base current (IBI_B) of 2 mA2\text{ mA} is applied. If the transistor has a common-emitter DC current gain (β\beta or hFEh_{FE}) of 5050, what is the resulting collector current (ICI_C) flowing through the transistor?

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Cevap: 100 mA100\text{ mA}

Cevap

The collector current (ICI_C) is 100 mA100\text{ mA}.
In the active region of a bipolar junction transistor, the collector current is directly proportional to the base current by the factor of DC current gain: IC=β×IBI_C = \beta \times I_B. Multiplying the base current of 2 mA2\text{ mA} by the gain of 5050 yields 100 mA100\text{ mA}.

Adım Adım Çözüm

1
Identify the given values and formula for transistor DC current gain in the active region.
Given IB=2 mAI_B = 2\text{ mA} and β=50\beta = 50. The governing formula is IC=β×IBI_C = \beta \times I_B.
Current gain (β\beta) represents the amplification factor between the controlling base current and the controlled collector current.
2
Substitute the measured base current and gain into the current equation.
IC=50×2 mA=100 mAI_C = 50 \times 2\text{ mA} = 100\text{ mA}.
Calculating the product gives the total current flowing through the collector terminal.

Anahtar Kavram

Bipolar Junction Transistor DC Current Gain (β\beta or hFEh_{FE})
Tahmini Süre:1m 0s
Soru 76Soru →

Match each switch configuration and electromechanical relay component with its primary function.

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Öğeler

SPST Switch
SPDT Switch
Relay Coil
Normally Open (NO) Contact

Eşleşmeler

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Cevap

SPST Switch matches with basic single-circuit on-off operation; SPDT Switch matches with directing one common terminal between two output paths; Relay Coil matches with generating a magnetic field to move the armature; Normally Open (NO) Contact matches with maintaining an open circuit until energized.
Each component is correctly matched to its defined operational role: an SPST switch opens or closes one path; an SPDT switch alternates between two paths; a relay coil uses current to create an electromagnetic field; and an NO contact stays open until coil actuation occurs.

Adım Adım Çözüm

1
Analyze switch pole and throw designations.
SPST (Single Pole, Single Throw) has one input and one output for simple on/off control. SPDT (Single Pole, Double Throw) routes one input to either of two outputs.
Poles define the number of separate circuits controlled, while throws define the number of output positions available per pole.
2
Analyze relay component functions and contact resting states.
The coil provides electromagnetic force to actuate the switch mechanism, while Normally Open contacts only close and allow current flow when this magnetic force is active.
Relay contacts are designated based on their state when the control coil is unpowered (de-energized).

Anahtar Kavram

Switch Nomenclature and Electromechanical Relay Operation
Tahmini Süre:45s
Soru 77Soru →

An ideal transformer has a primary coil with 600600 turns and a secondary coil with 150150 turns. The primary coil is connected to a 120 V120\text{ V} AC source, and the secondary coil is connected to a load consisting of two 15 Ω15\ \Omega resistors wired in parallel. What is the total current flowing through the primary coil?

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Cevap: 1 A1\text{ A}

Cevap

The total current flowing through the primary coil is 1 A1\text{ A}.
The correct answer synthesizes multiple principles. First, the transformer step-down ratio is 600:150600:150, or 4:14:1. This drops the primary 120 V120\text{ V} to a secondary 30 V30\text{ V}. Next, the two 15 Ω15\ \Omega resistors in parallel create an equivalent resistance of 7.5 Ω7.5\ \Omega. Using Ohm's Law (I=V/RI = V/R), the secondary current is 30 V/7.5 Ω=4 A30\text{ V} / 7.5\ \Omega = 4\text{ A}. Finally, because a transformer steps current inversely to voltage, a 4:14:1 voltage step-down means a 1:41:4 current step-up from primary to secondary. Therefore, the primary current is 4 A/4=1 A4\text{ A} / 4 = 1\text{ A}.

Adım Adım Çözüm

1
Calculate the turns ratio to determine the secondary voltage.
Np/Ns=600/150=4N_p/N_s = 600/150 = 4. Therefore, Vs=120 V/4=30 VV_s = 120\text{ V} / 4 = 30\text{ V}.
In a transformer, the voltage ratio is directly proportional to the turns ratio.
2
Determine the equivalent resistance of the secondary load.
For two equal resistors in parallel, Req=15 Ω/2=7.5 ΩR_{eq} = 15\ \Omega / 2 = 7.5\ \Omega.
Parallel branches provide multiple paths for current, reducing the total resistance of the circuit.
3
Apply Ohm's law to find the total secondary current.
Is=Vs/Req=30 V/7.5 Ω=4 AI_s = V_s / R_{eq} = 30\text{ V} / 7.5\ \Omega = 4\text{ A}.
The total current drawn by the load depends on the secondary voltage and the equivalent resistance of the load.
4
Calculate the primary current using the inverse turns ratio.
Ip=Is/(Np/Ns)=4 A/4=1 AI_p = I_s / (N_p / N_s) = 4\text{ A} / 4 = 1\text{ A}.
In an ideal transformer, power is conserved (Pp=PsP_p = P_s). If voltage steps down by a factor of 4, the current must step up by a factor of 4 from primary to secondary, making the primary current 1/4 of the secondary current.

Anahtar Kavram

Transformer turns ratio scaling for voltage and current, combined with parallel circuit analysis.
Soru 78Soru →

When inspecting a standard 14-pin Dual In-line Package (DIP) integrated circuit with the reference notch oriented at the top, which statement correctly describes the standard pinout numbering convention used to identify pin 1 and pin 14?

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Cevap: Pin 1 is at the top-left beside the notch, and numbering progresses counter-clockwise down the left side from pin 1 to 7, across to the bottom-right for pin 8, and up the right side to pin 14 at the top-right.

Cevap

Pin 1 is located at the top-left immediately adjacent to the notch, and numbering continues counter-clockwise down the left column (pins 1 through 7) and upward along the right column (pins 8 through 14), placing pin 14 at the top-right directly opposite pin 1.
For all standard Dual In-line Package (DIP) integrated circuits, placing the index notch at the top establishes pin 1 at the top-left. Numbering then advances counter-clockwise down the left row (pins 1 to 7 for a 14-pin IC), transitions across to the bottom-right pin (pin 8), and ascends the right row to pin 14 at the top-right.

Adım Adım Çözüm

1
Orient the integrated circuit package correctly.
The reference notch or alignment dot is positioned facing upward (top).
Standardized electronic manufacturing standards (JEDEC) require referencing the orientation marker before indexing lead pins.
2
Identify pin 1 based on the reference notch.
Pin 1 is the lead located immediately to the left of the notch in the top row.
By industry convention, pin 1 is always directly counter-clockwise adjacent to the top reference notch.
3
Trace the indexing sequence around the Dual In-line Package perimeter.
Pins 1 through 7 run down the left side, pin 8 is at the bottom-right, and pins 9 through 14 advance upward on the right side to pin 14 at the top-right.
DIP integrated circuits use a continuous counter-clockwise loop rather than parallel or alternating row numbering.

Anahtar Kavram

Dual In-line Package (DIP) Integrated Circuit Pin Numbering Convention
Tahmini Süre:1m 0s
Soru 79Soru →

Electronic systems utilize various solid-state semiconductor transistors tailored for specific switching, amplification, and sensing applications. Match each transistor type to its defining operating principle and physical characteristic.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Bipolar Junction Transistor (BJT)
Junction Field-Effect Transistor (JFET)
Metal-Oxide-Semiconductor FET (MOSFET)
Phototransistor

Eşleşmeler

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Cevap

Bipolar Junction Transistor (BJT) pairs with the current-controlled device using both electron and hole carriers; Junction Field-Effect Transistor (JFET) pairs with the voltage-controlled device using a reverse-biased PN junction; Metal-Oxide-Semiconductor FET (MOSFET) pairs with the insulated-gate component featuring high input impedance and an oxide dielectric; Phototransistor pairs with the optoelectronic component converting incident light into amplified collector current.
Each semiconductor device corresponds uniquely to its operating physics: BJTs are bipolar current-controlled devices; JFETs utilize reverse-biased PN junctions for channel modulation; MOSFETs employ an insulated dielectric gate for field-effect control; and phototransistors utilize optical stimulation to generate base-region carriers.

Adım Adım Çözüm

1
Identify the carrier conduction and control mechanism of the BJT
The BJT is a current-controlled bipolar device relying on both majority and minority carriers (electrons and holes).
The term bipolar explicitly indicates the participation of both carrier polarities, controlled by base current.
2
Differentiate between the field-effect transistor junction types (JFET vs. MOSFET)
The JFET relies on a direct reverse-biased PN gate junction, while the MOSFET incorporates an insulated oxide layer that eliminates DC gate current entirely.
The metal-oxide insulator in a MOSFET provides near-infinite input impedance compared to the reverse-biased PN junction of a JFET.
3
Distinguish the optoelectronic sensor category (Phototransistor)
The phototransistor operates by replacing or augmenting electrical base current with photon-generated charge carriers.
Light striking the transparent casing generates electron-hole pairs at the junction to initiate conduction.

Anahtar Kavram

Classification, control mechanisms, and structural properties of major transistor families
Tahmini Süre:1m 0s
Soru 80Soru →

In a multi-stage radio receiver, an electronics technician places a coupling capacitor in series along the signal line between two amplifier stages. What is the primary function of this capacitor regarding the combined Direct Current (DC) bias and Alternating Current (AC) signal?

Cevabı ve açıklamayı göster

Cevap: Permits the fluctuating AC signal to pass through while completely blocking the steady DC bias voltage.

Cevap

Permits the fluctuating AC signal to pass through while completely blocking the steady DC bias voltage.
A capacitor acts as an open circuit to steady Direct Current (DC) because the insulating dielectric stops continuous charge conduction once the plates reach the bias voltage level. Simultaneously, the alternating fluctuations of an AC signal continuously charge and discharge the plates, allowing the alternating signal to transfer cleanly to the next amplifier stage without shifting its DC bias point.

Adım Adım Çözüm

1
Analyze capacitor behavior in a steady Direct Current (DC) state.
Because the dielectric layer is an electrical insulator, steady DC charges the plates until the potential difference equals the supply voltage, reducing steady-state current to zero (XC=∞X_C = \infty at 0 Hz0\text{ Hz}). The capacitor acts as an open circuit to DC.
Determines how the DC operating bias of the first amplifier stage is isolated from the second stage.
2
Analyze capacitor behavior when exposed to an Alternating Current (AC) signal.
The alternating polarity causes continuous charging and discharging cycles, allowing the AC signal to transfer across the component with low capacitive reactance (XC=12πfCX_C = \frac{1}{2\pi f C}).
Determines how dynamic information and audio/RF waveforms propagate across the circuit.
3
Evaluate the combined circuit function of a series coupling capacitor.
The component blocks the steady DC bias voltage while coupling the alternating signal waveform directly to the next amplifier stage.
Confirms the core operational role of coupling capacitors in electronic signal chains.

Anahtar Kavram

Capacitor DC Blocking and AC Coupling
Tahmini Süre:1m 0s
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