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Difficulty: MediumVoltage and Electromotive Force (EMF)

Match each voltage-related electrical term on the left with its correct technical definition or operational characteristic on the right.

  • Electromotive Force (EMF)The total energy per unit charge supplied by an active source before internal losses occur
  • Voltage DropThe loss of electrical potential across a circuit component as current overcomes its resistance
  • Volt (V)The unit of electrical potential equivalent to one joule of energy per coulomb of charge (1 J/C1\text{ J/C})
  • VoltmeterA high-internal-resistance instrument connected in parallel across components to measure potential difference

Answer

Electromotive Force corresponds to the total energy per unit charge supplied by an active source; Voltage Drop corresponds to the loss of potential across a circuit component; Volt corresponds to one joule per coulomb; and Voltmeter corresponds to the high-internal-resistance instrument connected in parallel.
Each term accurately matches its foundational principle: EMF describes the electrical force provided by a source, voltage drop denotes the potential consumed across a load, the volt is the SI unit defining joules per coulomb, and a voltmeter is the high-impedance instrument used in parallel across components.

Step-by-Step Solution

1
Define Electromotive Force (EMF)
EMF represents the source voltage generated by converting chemical, mechanical, or thermal energy into electrical energy per unit charge.
An active energy source establishes the potential difference that pushes electrons through the external circuit.
2
Distinguish Voltage Drop across a load
Voltage drop reflects the potential energy consumed when charges traverse a resistive element.
Ohm's Law governs potential loss (V=IRV = IR) as electric energy is converted into heat, light, or work.
3
Identify the standard physical definition of the Volt
One volt (1 V1\text{ V}) is mathematically equivalent to one joule per coulomb (1 J/C1\text{ J/C}).
Voltage quantifies potential energy difference per unit electric charge.
4
Determine the operational method of a Voltmeter
A voltmeter measures potential difference between two nodes and requires a parallel connection with high internal resistance.
High impedance ensures the meter does not draw significant current from the branch under test.

Key Concept

Voltage represents electrical pressure and potential energy per unit charge, manifesting as source EMF, component voltage drops, and measured in volts using parallel-connected voltmeters.
Estimated Time:1m 0s
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Topics

Voltage and Electromotive Force (EMF)

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