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Maharashtra SSC Electronics Technology Pre-Voc/NSQF study materials
Maharashtra SSC Electronics Technology Pre-Voc/NSQF study resources

Maharashtra SSC Electronics Technology Pre-Voc/NSQF practice questions

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Question 1Basic Electrical and Electronic Fundamentals

In an Electronics Technology workshop, a student needs a fixed resistor whose value is read by the colour bands brown, black, red and gold. What is the nominal resistance and tolerance of this component?

  1. 120 Ω with ±10% tolerance
  2. 100 Ω with ±5% tolerance
  3. 1000 Ω with ±5% tolerance Correct answer.
  4. 1000 Ω with ±10% tolerance

Explanation

The four-band code reads the first two bands as significant digits, the third band as the number of zeros (multiplier), and the fourth band as tolerance. Brown = 1, black = 0, red = 2 zeros, giving 1000 Ω, and gold denotes ±5%.

Question 2Basic Electrical and Electronic Fundamentals

A technician connects a 12 V supply across a 6 Ω resistor in a basic practical circuit. Using Ohm's law, what current flows through the resistor?

  1. 18 A
  2. 0.5 A
  3. 72 A
  4. 2 A Correct answer.

Explanation

Ohm's law states I = V / R, so the current is 12 V divided by 6 Ω, which equals 2 A. The relationship is linear, so doubling the voltage would double the current while the resistance stays fixed.

Question 3Basic Electrical and Electronic Fundamentals

Which statement correctly describes the function of a capacitor in a DC circuit?

  1. It stores energy in an electric field and blocks steady direct current once charged. Correct answer.
  2. It converts alternating current into direct current by rectification.
  3. It provides a fixed voltage reference independent of supply variations.
  4. It stores energy in a magnetic field and opposes changes in current.

Explanation

A capacitor stores charge and energy in the electric field between its plates. When connected to a steady DC supply it charges up and then behaves as an open circuit, so no steady current flows, though it passes changing signals.

Question 4Basic Electrical and Electronic Fundamentals

In a workshop experiment a 9 V battery is connected to three resistors of 3 Ω, 6 Ω and 9 Ω in series. What is the total current drawn from the battery?

  1. 3 A
  2. 1.5 A
  3. 0.25 A
  4. 0.5 A Correct answer.

Explanation

In a series circuit the resistances add, giving 3 + 6 + 9 = 18 Ω. The current is then V / R = 9 V / 18 Ω = 0.5 A, and the same current flows through every resistor in the chain.

Question 5Basic Electrical and Electronic Fundamentals

Two resistors, 4 Ω and 12 Ω, are connected in parallel across a 12 V supply. What is the equivalent resistance of the combination?

  1. 3 Ω Correct answer.
  2. 8 Ω
  3. 16 Ω
  4. 48 Ω

Explanation

For two parallel resistors the product-over-sum rule gives (4 × 12) / (4 + 12) = 48 / 16 = 3 Ω. The equivalent resistance of a parallel network is always smaller than the smallest individual resistor, which confirms the answer.

Question 6Basic Electrical and Electronic Fundamentals

A diode is forward biased in a simple rectifier circuit built by a student. Which description of its behaviour is correct?

  1. It behaves as an open circuit in both directions at all voltages.
  2. It conducts heavily in reverse bias until breakdown occurs.
  3. It conducts equally in both directions regardless of polarity.
  4. It conducts easily once the forward voltage exceeds about 0.7 V for silicon. Correct answer.

Explanation

A forward-biased silicon diode begins to conduct appreciably when the applied voltage exceeds its barrier potential of roughly 0.7 V. Below that value the current is very small, and in reverse bias only a tiny leakage current flows.

Question 7Basic Electrical and Electronic Fundamentals

A transformer used in a power supply has 400 turns on its primary and 40 turns on its secondary. If the primary is connected to a 230 V AC supply, what is the secondary voltage?

  1. 23 V Correct answer.
  2. 11.5 V
  3. 230 V
  4. 2300 V

Explanation

The turns ratio is 400 : 40, or 10 : 1, so the secondary voltage is the primary voltage divided by 10. Dividing 230 V by 10 gives 23 V, which is the step-down output of this transformer.

Question 8Basic Electrical and Electronic Fundamentals

Which material property makes copper a preferred conductor for wiring in electronic equipment?

  1. Very high resistivity combined with high mechanical strength
  2. Low resistivity combined with good ductility Correct answer.
  3. High permeability combined with low conductivity
  4. Zero resistance at room temperature

Explanation

Copper has low resistivity, so it carries current with small losses, and it is ductile enough to be drawn into wire and bent during assembly. These two properties together explain its widespread use in connecting wires and PCB tracks.

Question 9Basic Electrical and Electronic Fundamentals

A 60 W lamp is operated on a 230 V AC mains supply. What is the approximate current drawn by the lamp?

  1. 3.83 A
  2. 0.06 A
  3. 0.26 A Correct answer.
  4. 13.8 A

Explanation

Electrical power is given by P = V × I, so the current is I = P / V. Dividing 60 W by 230 V gives about 0.26 A, which is the current the lamp draws from the mains.

Question 10Basic Electrical and Electronic Fundamentals

A student measures the resistance of a component with a multimeter set to the ohmmeter range while the circuit is still powered. Why is this practice incorrect?

  1. The ohmmeter applies its own test voltage, so external voltage gives false readings and can damage the meter. Correct answer.
  2. The ohmmeter range only works on inductors and cannot read resistors.
  3. The meter automatically switches to the voltmeter range and reads zero.
  4. The ohmmeter reads only alternating current resistance, so DC supplies do not matter.

Explanation

An ohmmeter measures resistance by applying a small internal voltage and sensing the resulting current. Any external supply in the circuit adds to this and corrupts the reading, and the injected current can also damage the instrument, so the circuit must be isolated before measuring.

Question 11Basic Electrical and Electronic Fundamentals

Which quantity is measured in coulombs in the SI system used in electronics?

  1. Potential difference
  2. Resistance
  3. Electric charge Correct answer.
  4. Electric current

Explanation

The coulomb is the SI unit of electric charge, defined as the charge carried by a current of one ampere for one second. Current, potential difference and resistance are measured in amperes, volts and ohms respectively.

Question 12Basic Electrical and Electronic Fundamentals

In a half-wave rectifier using a single diode, what is the output waveform when a sinusoidal AC input is applied?

  1. A steady DC level with no ripple
  2. A full sine wave with both halves present
  3. A square wave of the same frequency as the input
  4. One half of each input cycle, with the other half blocked Correct answer.

Explanation

A single diode conducts only during the half cycle in which it is forward biased, so only one half of each input cycle appears across the load. The other half is blocked, which is why the output is a pulsating DC with a gap between pulses.

Question 13Basic Electrical and Electronic Fundamentals

A resistor is marked 220 Ω with a silver fourth band. What does the silver band indicate about the resistor?

  1. Its tolerance is ±10% Correct answer.
  2. Its temperature coefficient is 10 ppm/°C
  3. Its tolerance is ±5%
  4. Its power rating is 10 W

Explanation

In the colour code the fourth band gives the tolerance, and silver corresponds to ±10%. The band does not encode power rating or temperature coefficient, which appear in data sheets or separate markings.

Question 14Basic Electrical and Electronic Fundamentals

A capacitor of 100 µF is charged to 10 V. What charge is stored on it?

  1. 0.1 µC
  2. 100 µC
  3. 10 µC
  4. 1000 µC Correct answer.

Explanation

The charge on a capacitor is Q = C × V, so 100 µF multiplied by 10 V gives 1000 µC, which equals 1 mC. The capacitance must be used in farads and the voltage in volts to obtain coulombs.

Question 15Basic Electrical and Electronic Fundamentals

Which arrangement converts a moving-coil galvanometer into a voltmeter with a wider range?

  1. A diode connected in series with the coil
  2. A high-value resistor connected in series with the coil Correct answer.
  3. A low-value shunt resistor connected in parallel with the coil
  4. A capacitor connected in parallel with the coil

Explanation

A voltmeter must draw very little current, so a high resistance is placed in series with the galvanometer coil to limit the current and drop most of the measured voltage. A parallel shunt lowers resistance and is used to make an ammeter instead.

Question 16Basic Electrical and Electronic Fundamentals

An LED is to be operated from a 5 V supply with a forward voltage of 2 V and a forward current of 10 mA. What series resistor is needed?

  1. 200 Ω
  2. 500 Ω
  3. 700 Ω
  4. 300 Ω Correct answer.

Explanation

The resistor must drop the difference between the supply and the LED forward voltage, that is 5 V − 2 V = 3 V. Using R = V / I with I = 10 mA = 0.01 A gives 3 / 0.01 = 300 Ω.

Question 17Basic Electrical and Electronic Fundamentals

In a series circuit containing a 10 Ω and a 20 Ω resistor, how does the current through the 10 Ω resistor compare with the current through the 20 Ω resistor?

  1. The current through the 10 Ω resistor is half as large.
  2. The current is the same through both resistors. Correct answer.
  3. The current through the 20 Ω resistor is twice as large.
  4. The current through the 10 Ω resistor is twice as large.

Explanation

In a series circuit there is only one path for the charge, so the same current flows through every component regardless of its resistance. The resistances affect the voltage drops, not the current.

Question 18Basic Electrical and Electronic Fundamentals

A student is asked to select a fuse for a 230 V appliance that draws about 2 A. Which fuse rating is the most appropriate choice?

  1. A 20 A fuse
  2. A 3 A fuse Correct answer.
  3. A 13 A fuse
  4. A 1 A fuse

Explanation

A fuse should carry the normal operating current without blowing but should melt on a modest overload. A 3 A fuse is just above the 2 A working current, while 1 A would blow in normal use and 13 A or 20 A would allow excessive current before clearing.

Question 19Basic Electrical and Electronic Fundamentals

Which property of a Zener diode makes it useful as a voltage regulator?

  1. It emits light when forward biased, indicating regulation.
  2. It stores charge like a small capacitor when reverse biased.
  3. It maintains a nearly constant reverse voltage over a range of reverse currents. Correct answer.
  4. It has a very low forward resistance that varies with temperature.

Explanation

A Zener diode is operated in reverse breakdown, where its voltage stays almost constant even as the reverse current changes. This steady breakdown voltage is used as a reference to regulate the output of a simple supply.

Question 20Basic Electrical and Electronic Fundamentals

Three 6 Ω resistors are connected in parallel. What is the equivalent resistance of the network?

  1. 2 Ω Correct answer.
  2. 6 Ω
  3. 3 Ω
  4. 18 Ω

Explanation

For n equal resistors in parallel the equivalent resistance is R / n, so 6 Ω divided by 3 gives 2 Ω. This is smaller than any single resistor, as expected for a parallel network.

Question 21Basic Electrical and Electronic Fundamentals

A 12 V battery delivers 0.5 A to a load. How much energy is converted by the load in 2 minutes?

  1. 24 J
  2. 1440 J
  3. 720 J Correct answer.
  4. 12 J

Explanation

Power is P = V × I = 12 × 0.5 = 6 W, and energy is power multiplied by time. Two minutes is 120 s, so the energy is 6 × 120 = 720 J.

Question 22Basic Electrical and Electronic Fundamentals

In a bridge rectifier used in a DC power supply, how many diodes conduct during each half cycle of the AC input?

  1. One diode
  2. Two diodes Correct answer.
  3. Four diodes
  4. Three diodes

Explanation

A bridge rectifier has four diodes, and in each half cycle one pair is forward biased while the other pair is reverse biased. Thus two diodes conduct at a time, and the conducting pair alternates every half cycle.

Question 23Basic Electrical and Electronic Fundamentals

Why is a capacitor connected across the output of a rectifier in a simple power supply?

  1. To step down the input AC voltage
  2. To increase the AC ripple on the output
  3. To convert the AC input into DC before the diodes
  4. To smooth the pulsating DC into a steadier voltage Correct answer.

Explanation

The capacitor charges at the peaks of the rectified waveform and discharges into the load between peaks, filling in the gaps. This smoothing action reduces ripple and gives a more nearly steady DC output.

Question 24Basic Electrical and Electronic Fundamentals

A coil has an inductance of 2 H and carries a current that changes at 3 A per second. What is the magnitude of the induced emf?

  1. 0.67 V
  2. 6 V Correct answer.
  3. 5 V
  4. 1.5 V

Explanation

The voltage across an inductor is V = L × (dI/dt), so 2 H multiplied by 3 A/s gives 6 V. The induced emf opposes the change in current, which is the self-induction effect.

Question 25Electronic Components and Devices

In the resistor colour code, a resistor marked brown, black, red, gold has a nominal value of 1 kΩ. What does the gold band indicate?

  1. A tolerance of ±10%
  2. A temperature coefficient of 100 ppm/K
  3. A tolerance of ±5% Correct answer.
  4. A voltage rating of 100 V

Explanation

The fourth band of a four-band resistor gives the tolerance, and gold always means plus or minus five percent. Silver would mean plus or minus ten percent, while a five-band resistor reserves a separate band for temperature coefficient. The value 1 kΩ comes from brown = 1, black = 0 and red = two zeros.

Question 26Electronic Components and Devices

A capacitor is marked 473K. What is its capacitance and tolerance?

  1. 47 nF, ±10% Correct answer.
  2. 47 pF, ±10%
  3. 4.7 nF, ±10%
  4. 0.47 µF, ±10%

Explanation

In the three-digit code the first two digits are significant figures and the third is the number of zeros in picofarads, so 473 means 47 000 pF, which is 47 nF. The letter K denotes plus or minus ten percent tolerance. Always convert to nanofarads or microfarads for practical use.

Question 27Electronic Components and Devices

Which property makes a diode suitable for rectification in a power supply?

  1. It stores charge between two plates
  2. It offers equal resistance in both directions
  3. It conducts easily in forward bias and blocks current in reverse bias Correct answer.
  4. It amplifies the input signal

Explanation

A p-n junction diode is a one-way valve: forward bias reduces the depletion barrier so current flows, while reverse bias widens it and only leakage flows. This unidirectional conduction lets a diode convert alternating current into pulsating direct current. Charge storage describes a capacitor, and amplification describes a transistor.

Question 28Electronic Components and Devices

What is the primary function of a transformer in an electronic circuit?

  1. To store energy in a magnetic field permanently
  2. To change AC voltage levels by mutual induction Correct answer.
  3. To smooth the ripple in a DC supply
  4. To convert AC into DC

Explanation

A transformer couples two windings through a shared magnetic core, so an alternating current in the primary induces an EMF in the secondary. The turns ratio sets whether the voltage steps up or steps down. It works only on AC, so it cannot by itself produce DC or remove ripple.

Question 29Electronic Components and Devices

Which standard package code identifies a plastic transistor outline with three leads commonly used for small-signal BJTs?

  1. SOT-223
  2. DO-41
  3. TO-92 Correct answer.
  4. DIP-8

Explanation

TO-92 is the familiar small plastic transistor package with a flat face and three in-line leads. DIP-8 is an eight-pin integrated-circuit package, SOT-223 is a surface-mount power package, and DO-41 is a cylindrical axial diode package. Package codes help a technician identify a device before soldering.

Question 30Electronic Components and Devices

Which material is a semiconductor commonly used for making diodes and transistors?

  1. Copper
  2. Silicon Correct answer.
  3. Mica
  4. Nichrome

Explanation

Silicon is a group-IV element whose four valence electrons form a stable lattice, and doping it with trivalent or pentavalent impurities creates p-type and n-type regions. That controlled doping is what makes p-n junctions possible. Copper is a conductor, mica an insulator, and nichrome a resistance alloy.

Question 31Electronic Components and Devices

What is the main purpose of a heat sink fitted to a power transistor?

  1. To increase the surface area for dissipating heat Correct answer.
  2. To filter supply ripple
  3. To increase the current gain of the transistor
  4. To protect the transistor from reverse voltage

Explanation

A power transistor dissipates heat in its junction, and the heat sink provides a larger surface plus fins so that heat passes to the surrounding air by convection. This keeps the junction temperature below its maximum rating. Gain, ripple filtering and reverse-voltage protection are electrical functions that a heat sink does not perform.

Question 32Electronic Components and Devices

A resistor has bands orange, orange, brown, gold. What is its value and tolerance?

  1. 33 Ω ±5%
  2. 3.3 kΩ ±5%
  3. 330 Ω ±5% Correct answer.
  4. 330 Ω ±10%

Explanation

Orange is 3 and brown is a multiplier of ten, so the value is 33 × 10 = 330 Ω. The gold band gives plus or minus five percent tolerance. Reading the multiplier band as a digit instead of a power of ten is the usual source of error.

Question 33Electronic Components and Devices

Two resistors of 220 Ω and 330 Ω are connected in parallel. What is the equivalent resistance?

  1. 110 Ω
  2. 275 Ω
  3. 132 Ω Correct answer.
  4. 550 Ω

Explanation

For two resistors in parallel, the product over the sum gives (220 × 330) ÷ (220 + 330) = 72 600 ÷ 550, which is about 132 Ω. The result is always smaller than the smallest branch resistance. Adding the values would apply only to a series connection.

Question 34Electronic Components and Devices

A silicon diode in a circuit has a forward voltage drop of about 0.7 V. If a 5 V supply feeds the diode through a 220 Ω series resistor, what current flows?

  1. About 22.7 mA
  2. About 25.9 mA
  3. About 19.5 mA Correct answer.
  4. About 7.0 mA

Explanation

The resistor sees the supply voltage minus the diode drop, so 5 − 0.7 = 4.3 V across 220 Ω. Dividing gives roughly 19.5 mA. Ignoring the diode drop and dividing 5 V by 220 Ω would overestimate the current.

Question 35Electronic Components and Devices

Which diode is designed to operate in reverse breakdown so that it holds a steady voltage across a load?

  1. Light-emitting diode
  2. Zener diode Correct answer.
  3. Photodiode
  4. Schottky diode

Explanation

A Zener diode is heavily doped so that controlled reverse breakdown occurs at a specified voltage, and in that region the voltage stays nearly constant as current varies. This makes it useful as a shunt voltage reference or regulator. LEDs emit light in forward bias, photodiodes respond to light, and Schottky diodes are valued for fast switching and low forward drop.

Question 36Electronic Components and Devices

What is the typical function of a light-emitting diode in a front-panel indicator circuit?

  1. To rectify the supply current
  2. To give a visual indication when forward current flows Correct answer.
  3. To step down the supply voltage
  4. To sense the ambient temperature

Explanation

In forward bias, electrons and holes recombine across the junction and release energy as photons, so the LED lights whenever current flows through it. A series resistor limits that current to a safe value. It does not rectify, sense temperature or regulate voltage.

Question 37Electronic Components and Devices

In an NPN transistor operating in the active region, which statement about its currents is correct?

  1. The collector current equals the base current plus the emitter current
  2. The emitter current equals the collector current plus the base current Correct answer.
  3. All three currents are always equal
  4. The base current equals the collector current plus the emitter current

Explanation

Applying Kirchhoff's current law to the transistor, the emitter carries the sum of the collector and base currents. Because the base current is very small, the collector current is only slightly less than the emitter current. This relationship underlies the current gain beta.

Question 38Electronic Components and Devices

Why is a capacitor connected across the output of a bridge rectifier?

  1. To convert AC into DC by itself
  2. To increase the reverse voltage rating of the diodes
  3. To limit the inrush current at switch-on
  4. To reduce ripple by charging and discharging Correct answer.

Explanation

The capacitor charges to the peak output voltage and then discharges slowly through the load between peaks, filling in the gaps of the pulsating waveform. This reduces ripple amplitude. Rectification itself is done by the diodes, not by the capacitor.

Question 39Electronic Components and Devices

What happens to the resistance of an NTC thermistor as its temperature rises?

  1. It stays constant
  2. It increases
  3. It first increases then falls to zero
  4. It decreases Correct answer.

Explanation

NTC stands for negative temperature coefficient, so the resistance falls as temperature rises because more charge carriers are released in the semiconductor material. This behaviour makes it useful for temperature sensing and inrush limiting. A PTC thermistor shows the opposite trend.

Question 40Electronic Components and Devices

A 5 V supply drives an LED with a forward drop of 2 V through a 150 Ω resistor. What is the LED current?

  1. 20 mA Correct answer.
  2. 10 mA
  3. 33 mA
  4. 13 mA

Explanation

The resistor drops the difference between the supply and the LED voltage, so 5 − 2 = 3 V appears across 150 Ω. Ohm's law then gives 3 ÷ 150 = 0.02 A, which is 20 mA. Using the full supply voltage would give the wrong, higher figure.

Question 41Electronic Components and Devices

What is the main advantage of a bridge rectifier over a centre-tap full-wave rectifier?

  1. It needs no centre-tapped transformer and uses the whole secondary winding Correct answer.
  2. It produces no ripple at all
  3. It works on direct current input
  4. It uses only two diodes

Explanation

A bridge uses four diodes to steer both half-cycles in the same direction through the load, so it does not require a centre tap and the full secondary voltage is used. A centre-tap design uses only half the winding at a time. Both designs still produce ripple that must be filtered.

Question 42Electronic Components and Devices

A relay is used in a control circuit. What is its essential working principle?

  1. A capacitor discharges through a coil to trip a contact
  2. A thermistor heats up and melts a fuse link
  3. An electromagnet moves a contact to switch a separate circuit Correct answer.
  4. A semiconductor junction rectifies the control signal

Explanation

Current through the relay coil creates a magnetic field that pulls the armature, closing or opening the contacts. Because the coil circuit and the contact circuit are electrically isolated, a small control current can switch a much larger load. This isolation is the main reason relays are used.

Question 43Electronic Components and Devices

A Zener diode rated 6.2 V is used as a shunt regulator with a series resistor from a 12 V supply. What is the voltage across the load?

  1. 0 V
  2. 5.8 V
  3. 12 V
  4. 6.2 V Correct answer.

Explanation

In reverse breakdown the Zener holds its nominal voltage across itself, and since the load is in parallel it sees the same 6.2 V. The series resistor absorbs the remaining 5.8 V. Regulation holds only while the Zener stays in breakdown and within its power rating.

Question 44Electronic Components and Devices

Which statement correctly describes the difference between intrinsic and extrinsic semiconductors?

  1. Intrinsic material is pure, while extrinsic material is deliberately doped Correct answer.
  2. Intrinsic material is doped, while extrinsic material is pure
  3. Intrinsic material is a metal, while extrinsic material is an insulator
  4. Intrinsic material conducts only when heated, while extrinsic material never conducts

Explanation

An intrinsic semiconductor is a pure crystal in which conduction depends on thermally generated electron-hole pairs. Extrinsic material has controlled donor or acceptor impurities added, which greatly increases conductivity and gives n-type or p-type behaviour. Doping is the basis of all junction devices.

Question 45Electronic Components and Devices

A transistor circuit has a collector current of 4 mA and a base current of 40 µA. What is the DC current gain?

  1. 0.01
  2. 100 Correct answer.
  3. 10
  4. 1000

Explanation

DC current gain beta is the collector current divided by the base current, so 4 mA ÷ 40 µA = 4000 µA ÷ 40 µA = 100. Both currents must be in the same unit before dividing. A gain of 100 is typical for a small-signal transistor.

Question 46Electronic Components and Devices

Why must a diode be connected in reverse across a relay coil driven by a transistor?

  1. To give the coil current a path when the transistor switches off Correct answer.
  2. To double the relay switching speed
  3. To reduce the coil resistance
  4. To increase the coil current during operation

Explanation

When the transistor turns off, the collapsing magnetic field of the coil generates a large reverse EMF that could exceed the transistor's breakdown voltage. The freewheeling diode, normally reverse biased, provides a path for that stored energy and clamps the spike. It has no effect on normal coil current.

Question 47Electronic Components and Devices

A 100 µF capacitor is charged to 10 V. How much energy does it store?

  1. 10 mJ
  2. 5 mJ Correct answer.
  3. 0.5 mJ
  4. 1 mJ

Explanation

Energy in a capacitor is half the capacitance times the square of the voltage, so 0.5 × 100 µF × (10 V)² = 0.5 × 100 × 10⁻⁶ × 100 = 5 × 10⁻³ J, which is 5 mJ. Remembering the factor of one half is essential.

Question 48Electronic Components and Devices

In a common-emitter amplifier, the input signal is applied to the base and the output is taken from the collector. What phase relationship exists between input and output at mid-band?

  1. The output is inverted, 180° out of phase Correct answer.
  2. The output lags by 45°
  3. The output is in phase with the input
  4. The output leads by 90°

Explanation

An increase in base current raises the collector current, which increases the drop across the collector resistor and therefore lowers the collector voltage. This gives the characteristic 180° phase inversion of the common-emitter stage. The common-collector stage, by contrast, is non-inverting.

Question 49Basic Electronic Circuits and Measurements

A resistor is marked with the colour bands brown, black, red, gold. What is its nominal resistance and tolerance?

  1. 1 kΩ with ±10% tolerance
  2. 10 Ω with ±5% tolerance
  3. 1 kΩ with ±5% tolerance Correct answer.
  4. 100 Ω with ±10% tolerance

Explanation

In the four-band code the first two bands give significant digits (brown = 1, black = 0), the third band is the multiplier (red = ×100), and the fourth gives tolerance (gold = ±5%). This yields 10 × 100 = 1000 Ω, i.e. 1 kΩ at ±5%.

Question 50Basic Electronic Circuits and Measurements

In a series circuit of three resistors carrying current, which quantity is the same through every resistor?

  1. The resistance of each resistor
  2. The voltage across each resistor
  3. The current through each resistor Correct answer.
  4. The power dissipated in each resistor

Explanation

A series circuit provides only one path for charge, so the same current flows through every element in the loop. Voltages, powers and resistances may all differ because they depend on each individual resistor value.