Ohm's Law

27 soru

Soru 1Soru →

Complete the statement regarding the electrical parameters of the DC circuit by calculating the missing resistance and current values.

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An indicator lamp with a constant resistance draws 150 mA150\text{ mA} when connected to a 24 V24\text{ V} direct current source. The internal resistance of the lamp is Ω\Omega, and if the supply voltage is increased to 36 V36\text{ V}, the current drawn by the lamp will increase to mA\text{mA}.
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Cevap

The internal resistance of the lamp is 160 Ω, and the new current at 36 V is 225 mA.
Converting 150 mA150\text{ mA} to standard amperes yields 0.15 A0.15\text{ A}. Using Ohm's law (R=V/IR = V / I), the internal resistance is 24 V/0.15 A=160 Ω24\text{ V} / 0.15\text{ A} = 160\ \Omega. When the voltage rises to 36 V36\text{ V}, applying I=V/RI = V / R produces 36 V/160 Ω=0.225 A36\text{ V} / 160\ \Omega = 0.225\text{ A}, which corresponds to 225 mA225\text{ mA}.

Adım Adım Çözüm

1
Convert the nominal current from milliamperes to base amperes
I1=150 mA=0.15 AI_1 = 150\text{ mA} = 0.15\text{ A}
Ohm's law requires base SI units (amperes, volts, ohms) for direct calculation.
2
Calculate the constant internal resistance using Ohm's law
R=V1I1=24 V0.15 A=160 ΩR = \frac{V_1}{I_1} = \frac{24\text{ V}}{0.15\text{ A}} = 160\ \Omega
Resistance equals voltage divided by current.
3
Calculate the new current at the elevated voltage level
I2=V2R=36 V160 Ω=0.225 A=225 mAI_2 = \frac{V_2}{R} = \frac{36\text{ V}}{160\ \Omega} = 0.225\text{ A} = 225\text{ mA}
Current across a fixed resistance is directly proportional to applied voltage (I=V/RI = V / R).

Anahtar Kavram

Ohm's Law (V=I×RV = I \times R) and Direct Proportionality in DC Circuits
Tahmini Süre:45s
Soru 2Soru →

An auxiliary electric bilge pump operates on a 12 V12\text{ V} DC power supply. If the internal electrical resistance of the pump motor is 6 Ω6\ \Omega, what is the steady-state current drawn by the pump during operation?

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Cevap: 2 A2\text{ A}

Cevap

The current drawn by the pump is 2 A2\text{ A}.
According to Ohm's Law, current (II) equals voltage (VV) divided by resistance (RR). Dividing the 12 V12\text{ V} supply by the 6 Ω6\ \Omega load resistance yields exactly 2 A2\text{ A}.

Adım Adım Çözüm

1
Identify the given circuit parameters and the formula to solve for unknown current.
Given: Voltage V=12 VV = 12\text{ V}, Resistance R=6 ΩR = 6\ \Omega. Ohm's Law states V=I×RV = I \times R, which rearranges to I=VRI = \frac{V}{R}.
Ohm's Law defines the fundamental mathematical relationship between voltage, current, and resistance in a direct current circuit.
2
Substitute the given values into the rearranged formula and compute the current.
I=12 V6 Ω=2 AI = \frac{12\text{ V}}{6\ \Omega} = 2\text{ A}.
Carrying out the division provides the magnitude of electron flow (amperage) through the load.

Anahtar Kavram

Ohm's Law formula for calculating current: I=VRI = \frac{V}{R}
Tahmini Süre:40s
Soru 3Soru →

In a test circuit, a 1.2 kΩ1.2\text{ k}\Omega resistor is connected across an adjustable DC power supply. When the supply voltage is increased by 18 V18\text{ V}, the current through the resistor reaches 35 mA35\text{ mA}. What was the initial current flowing through the resistor in milliamperes (mA\text{mA})?

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Cevap: 20

Cevap

The initial current flowing through the resistor was 20 mA20\text{ mA}.
Applying Ohm's Law (I=VRI = \frac{V}{R}), an 18 V18\text{ V} voltage increase across a 1.2 kΩ1.2\text{ k}\Omega (1200 Ω1{}200\ \Omega) resistor causes a current increase of ΔI=18 V1200 Ω=0.015 A=15 mA\Delta I = \frac{18\text{ V}}{1{}200\ \Omega} = 0.015\text{ A} = 15\text{ mA}. Subtracting this 15 mA15\text{ mA} change from the final current of 35 mA35\text{ mA} yields an initial current of 20 mA20\text{ mA}.

Adım Adım Çözüm

1
Convert resistance from kilohms (kΩk\Omega) to ohms (Ω\Omega).
R=1.2 kΩ=1200 ΩR = 1.2\text{ k}\Omega = 1{}200\ \Omega
Ohm's Law calculations require standard base SI units (VV in volts, II in amperes, RR in ohms).
2
Calculate the increase in current (ΔI\Delta I) resulting from the 18 V18\text{ V} voltage increase.
ΔI=ΔVR=18 V1200 Ω=0.015 A=15 mA\Delta I = \frac{\Delta V}{R} = \frac{18\text{ V}}{1{}200\ \Omega} = 0.015\text{ A} = 15\text{ mA}
According to Ohm's Law (I=VRI = \frac{V}{R}), an increase in voltage produces a directly proportional increase in current across a constant resistance.
3
Find the initial current by subtracting the current increase from the final current.
Iinitial=35 mA−15 mA=20 mAI_{\text{initial}} = 35\text{ mA} - 15\text{ mA} = 20\text{ mA}
The final current represents the sum of the initial current and the incremental current produced by the added voltage.

Anahtar Kavram

Ohm's Law defines the direct relationship between voltage and current across a constant resistance (I=VRI = \frac{V}{R}), meaning a change in voltage causes a proportional change in current.

Alternatif Yöntem

Calculate the final voltage first: Vfinal=Ifinal×R=0.035 A×1200 Ω=42 VV_{\text{final}} = I_{\text{final}} \times R = 0.035\text{ A} \times 1{}200\ \Omega = 42\text{ V}. Then subtract the 18 V18\text{ V} increase to find the initial voltage: Vinitial=42 V−18 V=24 VV_{\text{initial}} = 42\text{ V} - 18\text{ V} = 24\text{ V}. Finally, compute the initial current: Iinitial=24 V1200 Ω=0.020 A=20 mAI_{\text{initial}} = \frac{24\text{ V}}{1{}200\ \Omega} = 0.020\text{ A} = 20\text{ mA}.
Tahmini Süre:50s
Soru 4Soru →

A direct current (DC) relay coil with a fixed resistance draws 30 mA30\text{ mA} when connected across an 18 V18\text{ V} power supply. When the same relay coil is connected to a different DC power supply, an ammeter measures a current flow of 75 mA75\text{ mA} through the coil. What is the voltage of the second power supply?

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Cevap: 45 V45\text{ V}

Cevap

45 V45\text{ V}
The correct answer is determined by using Ohm's law (R=VIR = \frac{V}{I}) to find the coil's fixed resistance from the initial state (R=18 V0.030 A=600 ΩR = \frac{18\text{ V}}{0.030\text{ A}} = 600\,\Omega) and then determining the new voltage (V=0.075 A×600 Ω=45 VV = 0.075\text{ A} \times 600\,\Omega = 45\text{ V}).

Adım Adım Çözüm

1
Convert the initial current from milliamperes to amperes and calculate the resistance of the relay coil using Ohm's law (R=VIR = \frac{V}{I}).
I1=30 mA=0.030 AI_1 = 30\text{ mA} = 0.030\text{ A}; R=18 V0.030 A=600 ΩR = \frac{18\text{ V}}{0.030\text{ A}} = 600\,\Omega
The resistance of the coil remains constant regardless of the applied supply voltage.
2
Convert the second current reading to amperes and calculate the new supply voltage using Ohm's law (V=I×RV = I \times R).
I2=75 mA=0.075 AI_2 = 75\text{ mA} = 0.075\text{ A}; V2=0.075 A×600 Ω=45 VV_2 = 0.075\text{ A} \times 600\,\Omega = 45\text{ V}
Ohm's law states that the potential difference across a resistor equals current multiplied by resistance.

Anahtar Kavram

Direct proportionality between voltage and current across a fixed resistance (V=I×RV = I \times R) and metric unit conversion.
Tahmini Süre:45s
Soru 5Soru →

An electrical technician is analyzing a perfectly ohmic heating element in a circuit. During initial operation, when an unknown voltage VV is applied, the element draws a current of 45 mA45 \text{ mA}. The technician notes that if the applied voltage is increased by exactly 500 mV500 \text{ mV}, the current drawn by the element increases by 2.5 mA2.5 \text{ mA}. Assuming the element's resistance remains completely constant throughout the test, what was the original applied voltage VV?

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Cevap: 9 V

Cevap

9 V
For an ohmic component, resistance (RR) is constant. This means the change in voltage is directly proportional to the change in current. The resistance can be found using the changes: R=ΔV/ΔIR = \Delta V / \Delta I. After converting to base units, R=0.5 V/0.0025 A=200 ΩR = 0.5 \text{ V} / 0.0025 \text{ A} = 200 \, \Omega. Using Ohm's Law (V=I×RV = I \times R), the original voltage is the original current (0.045 A0.045 \text{ A}) multiplied by this resistance, resulting in 0.045 A×200 Ω=9 V0.045 \text{ A} \times 200 \, \Omega = 9 \text{ V}.

Adım Adım Çözüm

1
Identify the relationship between the change in voltage (ΔV) and the change in current (ΔI).
R=ΔVΔIR = \frac{\Delta V}{\Delta I}
For a perfectly ohmic component, the resistance is constant. This means the slope of the voltage-current relationship defines the resistance.
2
Convert the change values into standard base units (Volts and Amperes) and calculate the resistance.
ΔV=500 mV=0.5 V\Delta V = 500 \text{ mV} = 0.5 \text{ V}, and ΔI=2.5 mA=0.0025 A\Delta I = 2.5 \text{ mA} = 0.0025 \text{ A}. R=0.5 V0.0025 A=200 ΩR = \frac{0.5 \text{ V}}{0.0025 \text{ A}} = 200 \, \Omega
Standardizing metric prefixes prevents decimal shift errors before applying Ohm's Law.
3
Apply Ohm's Law to the original state to find the initial voltage.
V=Ioriginal×R=0.045 A×200 Ω=9 VV = I_{original} \times R = 0.045 \text{ A} \times 200 \, \Omega = 9 \text{ V}
Multiplying the originally measured current by the established component resistance yields the original voltage applied.

Anahtar Kavram

Applying Ohm's Law using proportional changes (ΔV and ΔI) while accurately managing metric prefix conversions.
Soru 6Soru →

An electronics technician is testing a DC bias circuit containing a fixed resistor connected to an adjustable DC power supply. When the supply voltage is set to 28 V28\text{ V}, the circuit ammeter measures a current of 3.5 mA3.5\text{ mA}. To increase the current flow through the resistor to 11 mA11\text{ mA}, what must the power supply voltage be set to?

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Cevap: 88 V88\text{ V}

Cevap

The power supply voltage must be set to 88 V88\text{ V}.
The power supply must be set to 88 V88\text{ V}. First, determine the component's constant resistance: R=28 V3.5 mA=8 kΩR = \frac{28\text{ V}}{3.5\text{ mA}} = 8\text{ k}\Omega. Next, apply Ohm's Law to find the voltage required for the target current: V=11 mA×8 kΩ=88 VV = 11\text{ mA} \times 8\text{ k}\Omega = 88\text{ V}. Alternatively, using direct proportionality: V2=28 V×(11 mA3.5 mA)=88 VV_2 = 28\text{ V} \times \left(\frac{11\text{ mA}}{3.5\text{ mA}}\right) = 88\text{ V}.

Adım Adım Çözüm

1
Calculate the fixed resistance using the initial voltage and current measurements.
R=V1I1=28 V3.5 mA=28 V0.0035 A=8000 Ω=8 kΩR = \frac{V_1}{I_1} = \frac{28\text{ V}}{3.5\text{ mA}} = \frac{28\text{ V}}{0.0035\text{ A}} = 8{}000\,\Omega = 8\text{ k}\Omega
Ohm's Law defines resistance as the ratio of voltage to current (R=VIR = \frac{V}{I}).
2
Calculate the new voltage required to produce 11 mA11\text{ mA} through the 8 kΩ8\text{ k}\Omega resistor.
V2=I2×R=0.011 A×8000 Ω=88 VV_2 = I_2 \times R = 0.011\text{ A} \times 8{}000\,\Omega = 88\text{ V}
Applying Ohm's Law in the form V=I×RV = I \times R determines the potential difference needed for the desired current.

Anahtar Kavram

Ohm's Law defines the fundamental linear relationship between voltage, current, and resistance in a DC circuit (V=I×RV = I \times R). In a circuit with constant resistance, voltage is directly proportional to current.

Alternatif Yöntem

Because resistance is constant, voltage is directly proportional to current: V2=V1×I2I1=28 V×11 mA3.5 mA=28×227=4×22=88 VV_2 = V_1 \times \frac{I_2}{I_1} = 28\text{ V} \times \frac{11\text{ mA}}{3.5\text{ mA}} = 28 \times \frac{22}{7} = 4 \times 22 = 88\text{ V}.
Tahmini Süre:45s
Soru 7Soru →

A DC cooling fan installed in an equipment enclosure has an internal resistance of 16 Ω16\ \Omega and draws a steady current of 1.5 A1.5\text{ A} during normal operation. According to Ohm's law, what is the voltage drop across the fan in volts (V\text{V})?

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Cevap: 24

Cevap

24 V
According to Ohm's law, voltage (VV) is found by multiplying current (II) by resistance (RR). With a current of 1.5 A1.5\text{ A} and a resistance of 16 Ω16\ \Omega, the voltage is 1.5×16=24 V1.5 \times 16 = 24\text{ V}.

Adım Adım Çözüm

1
Identify the known electrical quantities from the problem statement.
I=1.5 AI = 1.5\text{ A} and R=16 ΩR = 16\ \Omega
Ohm's law requires current and resistance values to calculate voltage.
2
State Ohm's law formula arranged to solve for voltage (VV).
V=I×RV = I \times R
The potential difference across a resistive element is directly proportional to the product of current and resistance.
3
Multiply the current by the resistance to find the voltage.
V=1.5 A×16 Ω=24 VV = 1.5\text{ A} \times 16\ \Omega = 24\text{ V}
Performing the multiplication yields the potential difference in volts.

Anahtar Kavram

Ohm's Law (V=I×RV = I \times R)
Tahmini Süre:30s
Soru 8Soru →

An electronics technician is testing an aircraft panel indicator circuit. When connected to a 24 V24\text{ V} DC power supply, the circuit draws a steady current of 4 A4\text{ A}. What is the resistance of the circuit, and what current will flow if the supply voltage is reduced to 12 V12\text{ V}?

Aşağıdaki boşlukları doldurun

According to Ohm's Law, the resistance of the circuit is Ω\Omega, and when the voltage is decreased to 12 V12\text{ V}, the new current drawn by the circuit is A\text{A}.
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Cevap

The resistance of the circuit is 6 Ω6\ \Omega and the current under the reduced voltage is 2 A2\text{ A}.
Applying Ohm's Law, the resistance is found by dividing the initial voltage by the initial current (R=24 V4 A=6 ΩR = \frac{24\text{ V}}{4\text{ A}} = 6\ \Omega). Keeping this resistance constant, halving the voltage to 12 V12\text{ V} results in half the current (I=12 V6 Ω=2 AI = \frac{12\text{ V}}{6\ \Omega} = 2\text{ A}).

Adım Adım Çözüm

1
Calculate the circuit resistance using Ohm's Law with the initial parameters (V1=24 VV_1 = 24\text{ V}, I1=4 AI_1 = 4\text{ A}).
R=V1I1=24 V4 A=6 ΩR = \frac{V_1}{I_1} = \frac{24\text{ V}}{4\text{ A}} = 6\ \Omega
Ohm's Law states that resistance equals voltage divided by current (R=VIR = \frac{V}{I}).
2
Determine the new current when the voltage is adjusted to V2=12 VV_2 = 12\text{ V} across the constant 6 Ω6\ \Omega resistance.
I2=V2R=12 V6 Ω=2 AI_2 = \frac{V_2}{R} = \frac{12\text{ V}}{6\ \Omega} = 2\text{ A}
Current is directly proportional to voltage for a fixed resistance (I=VRI = \frac{V}{R}).

Anahtar Kavram

Ohm's Law expresses the fundamental relationship among voltage, current, and resistance: V=I×RV = I \times R, I=VRI = \frac{V}{R}, and R=VIR = \frac{V}{I}.
Tahmini Süre:45s
Soru 9Soru →

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 10Soru →

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 11Soru →

A 36 V36\text{ V} DC control circuit supplies power to a single heating element. An inline ammeter measures a steady current flow of 3 A3\text{ A} through the circuit. What is the electrical resistance of the heating element in ohms?

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Cevap: 12

Cevap

12 ohms
According to Ohm's Law, resistance equals voltage divided by current (R=VIR = \frac{V}{I}). Dividing the source voltage of 36 V36\text{ V} by the current of 3 A3\text{ A} yields 12 Ω12\ \Omega.

Adım Adım Çözüm

1
Identify the known electrical values provided in the problem
Voltage (VV) = 36 V36\text{ V}, Current (II) = 3 A3\text{ A}
Ohm's Law relates potential difference, current flow, and circuit resistance.
2
Rearrange Ohm's Law to express resistance in terms of voltage and current
R=VIR = \frac{V}{I}
Resistance is defined as the ratio of voltage across a component to the current flowing through it.
3
Substitute the numerical values into the equation and solve
R=36 V3 A=12 ΩR = \frac{36\text{ V}}{3\text{ A}} = 12\ \Omega
Dividing 36 by 3 gives the resistance directly in ohms.

Anahtar Kavram

Ohm's Law states that the current through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance (V=I×RV = I \times R, which rearranges to R=VIR = \frac{V}{I}).
Tahmini Süre:30s
Soru 12Soru →

An electric horn connected to a 12 V12\text{ V} direct current (DC) automotive battery has an internal resistance of 3 Ω3\ \Omega. What is the steady current flowing through the horn circuit? Complete the statement below.

Aşağıdaki boşlukları doldurun

According to Ohm's law, the current flowing through the horn is amperes.
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Cevap

4 amperes (or 4)
According to Ohm's law, current is calculated using the formula I=VRI = \frac{V}{R}. Dividing the applied voltage (12 V12\text{ V}) by the circuit resistance (3 Ω3\ \Omega) gives a current of 4 A4\text{ A}.

Adım Adım Çözüm

1
Identify the given electrical parameters from the problem statement
Voltage (VV) = 12 V12\text{ V}, Resistance (RR) = 3 Ω3\ \Omega
Ohm's law relates voltage, current, and resistance in a closed DC circuit.
2
State Ohm's law rearranged to solve for current (II)
I=VRI = \frac{V}{R}
Current is directly proportional to voltage and inversely proportional to resistance.
3
Substitute the given numerical values into the formula and calculate
I=12 V3 Ω=4 AI = \frac{12\text{ V}}{3\ \Omega} = 4\text{ A}
Dividing 1212 volts by 33 ohms yields 44 amperes.

Anahtar Kavram

Ohm's Law states that current (II) equals voltage (VV) divided by resistance (RR).
Tahmini Süre:45s
Soru 13Soru →

A technician measures a steady current of 50 mA50\text{ mA} flowing through a 120 Ω120\ \Omega fixed resistor in a signal conditioning module. What is the voltage drop across the resistor?

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Cevap: 6 V6\text{ V}

Cevap

6 V6\text{ V}
According to Ohm's law, the voltage drop across a component is determined by multiplying current by resistance (V=I×RV = I \times R). Converting 50 mA50\text{ mA} to 0.05 A0.05\text{ A} and multiplying by 120 Ω120\ \Omega gives 6 V6\text{ V}.

Adım Adım Çözüm

1
Convert the current from milliamperes (mA) to amperes (A).
50 mA=0.05 A50\text{ mA} = 0.05\text{ A}
Standard electrical formulas require current in amperes.
2
Apply Ohm's law formula for voltage (V=I×RV = I \times R).
V=0.05 A×120 Ω=6 VV = 0.05\text{ A} \times 120\ \Omega = 6\text{ V}
Voltage across a resistor equals the product of current and resistance.

Anahtar Kavram

Ohm's Law states that voltage is equal to current multiplied by resistance (V=I×RV = I \times R).
Tahmini Süre:45s
Soru 14Soru →

In an auxiliary radio circuit, a direct-current source applies 24 V24\text{ V} across a fixed resistor, producing a measured current flow of 8 mA8\text{ mA}. What is the resistance of the component?

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Cevap: 3000 Ω3{}000\ \Omega

Cevap

3000 Ω3{}000\ \Omega
Applying Ohm's Law (R=VIR = \frac{V}{I}) with the current converted to amperes (8 mA=0.008 A8\text{ mA} = 0.008\text{ A}) gives 24 V0.008 A=3000 Ω\frac{24\text{ V}}{0.008\text{ A}} = 3{}000\ \Omega.

Adım Adım Çözüm

1
Convert the current from milliamperes (mA) to base amperes (A)
8 mA=8×10−3 A=0.008 A8\text{ mA} = 8 \times 10^{-3}\text{ A} = 0.008\text{ A}
Ohm's Law calculations require current in base units of amperes.
2
Apply Ohm's Law to solve for resistance (RR)
R=VI=24 V0.008 A=3000 ΩR = \frac{V}{I} = \frac{24\text{ V}}{0.008\text{ A}} = 3{}000\ \Omega
Resistance equals voltage divided by current.

Anahtar Kavram

Ohm's Law defines the direct relationship between voltage, current, and resistance in a DC circuit (R=VIR = \frac{V}{I}).
Tahmini Süre:45s
Soru 15Soru →

An electromagnetic security gate lock operates on an 18 V18\text{ V} direct-current (DC) power source. When fully energized, the lock draws a steady current of 250 mA250\text{ mA}. What is the electrical resistance of the lock in ohms (Ω\Omega)?

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Cevap: 72

Cevap

The electrical resistance of the electromagnetic lock is 72 Ω72\ \Omega.
According to Ohm's Law (V=I×RV = I \times R), resistance is found by dividing the potential difference by the current (R=VIR = \frac{V}{I}). Converting 250 mA250\text{ mA} to 0.25 A0.25\text{ A} and dividing 18 V18\text{ V} by 0.25 A0.25\text{ A} yields exactly 72 Ω72\ \Omega.

Adım Adım Çözüm

1
Convert the current measurement from milliamperes (mA\text{mA}) to amperes (A\text{A}).
I=250 mA=0.25 AI = 250\text{ mA} = 0.25\text{ A}
Ohm's Law calculations require current in base SI units (amperes) to yield resistance in ohms.
2
Rearrange Ohm's Law (V=I×RV = I \times R) to isolate resistance (RR).
R=VIR = \frac{V}{I}
Resistance is equal to the applied electromotive force (voltage) divided by the resulting current flow.
3
Substitute the given voltage and converted current into the formula and solve.
R=18 V0.25 A=72 ΩR = \frac{18\text{ V}}{0.25\text{ A}} = 72\ \Omega
Dividing 18 V18\text{ V} by 0.25 A0.25\text{ A} gives the total circuit resistance in ohms.

Anahtar Kavram

Ohm's Law states that resistance (RR) equals voltage (VV) divided by current (II), represented by the formula R=VIR = \frac{V}{I}.
Tahmini Süre:45s
Soru 16Soru →

A telemetry sensor on an unmanned aerial vehicle is connected to a 15 V15\text{ V} direct-current (DC) power supply. If the sensor circuit has an effective resistance of 2.5 kΩ2.5\text{ k}\Omega, what is the steady current flowing through the circuit in milliamperes (mA\text{mA})?

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Cevap: 6 mA6\text{ mA}

Cevap

The steady current flowing through the sensor circuit is 6 mA6\text{ mA}.
According to Ohm's Law, current equals voltage divided by resistance (I=VRI = \frac{V}{R}). Converting 2.5 kΩ2.5\text{ k}\Omega to 2500 Ω2{}500\ \Omega gives I=15 V2500 Ω=0.006 AI = \frac{15\text{ V}}{2{}500\ \Omega} = 0.006\text{ A}, which equals 6 mA6\text{ mA}.

Adım Adım Çözüm

1
Convert the resistance value from kilohms (kΩ\text{k}\Omega) to base ohms (Ω\Omega).
R=2.5 kΩ=2.5×103 Ω=2500 ΩR = 2.5\text{ k}\Omega = 2.5 \times 10^3\ \Omega = 2{}500\ \Omega
Ohm's Law calculations require base electrical units (volts, amperes, and ohms).
2
Apply Ohm's Law to solve for current in amperes (I=VRI = \frac{V}{R}).
I=15 V2500 Ω=0.006 AI = \frac{15\text{ V}}{2{}500\ \Omega} = 0.006\text{ A}
Current is directly proportional to voltage and inversely proportional to resistance.
3
Convert the resulting current from amperes (A\text{A}) to milliamperes (mA\text{mA}).
I=0.006 A×1000 mA/A=6 mAI = 0.006\text{ A} \times 1{}000\text{ mA/A} = 6\text{ mA}
The question asks for the final answer in milliamperes.

Anahtar Kavram

Ohm's Law defines the relationship between voltage, current, and resistance (I=VRI = \frac{V}{R}).
Tahmini Süre:45s
Soru 17Soru →

An avionics technician is analyzing a direct-current (DC) subassembly with an applied voltage of 36 V36\text{ V} across a load resistor rated at 1.8 kΩ1.8\text{ k}\Omega. What is the resistance in ohms and the resulting current in milliamperes? Fill in the blanks below to complete the circuit analysis.

Aşağıdaki boşlukları doldurun

The total resistance of the load is Ω\Omega, and the steady current flowing through the circuit is mA\text{mA}.
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Cevap

The resistance is 1800 Ω and the current is 20 mA.
Converting 1.8 kΩ1.8\text{ k}\Omega to base units gives 1800 Ω1800\ \Omega. Dividing the applied voltage of 36 V36\text{ V} by 1800 Ω1800\ \Omega yields 0.02 A0.02\text{ A}, which corresponds to 20 mA20\text{ mA}.

Adım Adım Çözüm

1
Convert the load resistance from kilohms (kΩ) to ohms (Ω)
R=1.8 kΩ=1.8×1000 Ω=1800 ΩR = 1.8\text{ k}\Omega = 1.8 \times 1000\ \Omega = 1800\ \Omega
Standard electrical calculations using Ohm's Law require base units of ohms, volts, and amperes.
2
Apply Ohm's Law (I=VRI = \frac{V}{R}) to calculate the circuit current in amperes
I=36 V1800 Ω=0.02 AI = \frac{36\text{ V}}{1800\ \Omega} = 0.02\text{ A}
Current is directly proportional to voltage and inversely proportional to resistance.
3
Convert the current from amperes (A) to milliamperes (mA)
I=0.02 A×1000 mA/A=20 mAI = 0.02\text{ A} \times 1000\text{ mA/A} = 20\text{ mA}
The required unit for the current blank is milliamperes.

Anahtar Kavram

Ohm's Law (I=VRI = \frac{V}{R}) and metric prefix conversions (kilo- and milli-).
Tahmini Süre:45s
Soru 18Soru →

A technician is testing a direct-current (DC) indicator lamp assembly in an armored vehicle. The lamp is connected to a 24 V24\text{ V} power supply and draws a steady current of 75 mA75\text{ mA}. What is the total electrical resistance of the lamp assembly?

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Cevap: 320 Ω320\ \Omega

Cevap

The total resistance of the lamp assembly is 320 Ω320\ \Omega.
According to Ohm's Law (V=I×RV = I \times R), resistance equals voltage divided by current (R=VIR = \frac{V}{I}). Converting 75 mA75\text{ mA} to 0.075 A0.075\text{ A} and dividing 24 V24\text{ V} by 0.075 A0.075\text{ A} yields 320 Ω320\ \Omega.

Adım Adım Çözüm

1
Convert the measured current from milliamperes (mA\text{mA}) to base amperes (A\text{A}).
I=75 mA=751000 A=0.075 AI = 75\text{ mA} = \frac{75}{1000}\text{ A} = 0.075\text{ A}
Ohm's Law calculations require standard SI units (amperes) to yield resistance in ohms.
2
Rearrange Ohm's Law (V=I×RV = I \times R) to solve for resistance (R=VIR = \frac{V}{I}) and substitute the known values.
R=24 V0.075 A=320 ΩR = \frac{24\text{ V}}{0.075\text{ A}} = 320\ \Omega
Dividing the applied voltage by the circuit current gives the total resistance.

Anahtar Kavram

Ohm's Law defines the relationship between voltage, current, and resistance (V=I×RV = I \times R, rearranged as R=VIR = \frac{V}{I}). Current must always be converted to base amperes before computing resistance.
Tahmini Süre:45s
Soru 19Soru →

An aircraft instrument panel illumination circuit is connected to a 28 V28\text{ V} direct-current (DC) power source. A multimeter measures a steady current flow of 350 mA350\text{ mA} through the circuit. What is the total electrical resistance of the circuit in ohms (Ω\Omega)?

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Cevap: 80

Cevap

The total electrical resistance of the circuit is 80 Ω80\ \Omega.
According to Ohm's Law, resistance equals voltage divided by current (R=VIR = \frac{V}{I}). Converting 350 mA350\text{ mA} to amperes yields 0.35 A0.35\text{ A}. Dividing 28 V28\text{ V} by 0.35 A0.35\text{ A} gives the correct resistance of 80 Ω80\ \Omega.

Adım Adım Çözüm

1
Convert the current from milliamperes to amperes
I=350 mA=0.35 AI = 350\text{ mA} = 0.35\text{ A}
Ohm's Law calculations require current to be expressed in standard amperes.
2
Apply Ohm's Law formula solved for resistance
R=VI=28 V0.35 A=80 ΩR = \frac{V}{I} = \frac{28\text{ V}}{0.35\text{ A}} = 80\ \Omega
Dividing the applied electromotive force by the current flow yields total circuit resistance.

Anahtar Kavram

Calculating resistance using Ohm's Law (R=VIR = \frac{V}{I}) with metric prefix conversion (1 A=1000 mA1\text{ A} = 1{}000\text{ mA}).
Tahmini Süre:45s
Soru 20Soru →

A technician is servicing a communications shelter ventilation fan controller that operates on a 48 V48\text{ V} direct-current (DC) power supply. A diagnostic test shows that the control circuit's primary sensing resistor has a resistance of 1.2 kΩ1.2\text{ k}\Omega. What is the current flowing through this resistor?

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Cevap: 40 mA40\text{ mA}

Cevap

40 mA40\text{ mA}
According to Ohm's Law, current is calculated by dividing voltage by resistance (I=VRI = \frac{V}{R}). First converting 1.2 kΩ1.2\text{ k}\Omega to 1200 Ω1200\ \Omega gives I=48 V1200 Ω=0.04 AI = \frac{48\text{ V}}{1200\ \Omega} = 0.04\text{ A}, which is equivalent to 40 mA40\text{ mA}.

Adım Adım Çözüm

1
Convert the resistance value from kilohms (kΩ\text{k}\Omega) to base ohms (Ω\Omega).
R=1.2 kΩ=1.2×1000 Ω=1200 ΩR = 1.2\text{ k}\Omega = 1.2 \times 1000\ \Omega = 1200\ \Omega
Standard electrical calculations using Ohm's Law require base units of volts, amperes, and ohms.
2
Apply Ohm's Law (I=VRI = \frac{V}{R}) to solve for the circuit current.
I=48 V1200 Ω=0.04 AI = \frac{48\text{ V}}{1200\ \Omega} = 0.04\text{ A}
Current equals voltage divided by resistance.
3
Convert the current in amperes to milliamperes (mA\text{mA}).
0.04 A×1000 mA/A=40 mA0.04\text{ A} \times 1000\text{ mA/A} = 40\text{ mA}
The answer choices are expressed in milliamperes.

Anahtar Kavram

Ohm's Law (I=VRI = \frac{V}{R}) and metric prefix conversions
Tahmini Süre:45s
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