What is the definition of "direct current"?
A current formed when electrons flow in one continuous direction.

Learn more about direct current in the class Electricity Fundamentals 160 below.

Shop Essentials (Applied Mathematics) Training

Class Information
Shop Essentials (Applied Mathematics) Training Tooling U-SME classes are offered at the beginner, intermediate, and advanced levels. The typical class consists of 12 to 25 lessons and will take approximately one hour to complete.
Class Name:Electricity Fundamentals 160
Description:This class describes the basic elements of electricity and how it works.
Number of Lessons:15
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Class Outline
  • Introduction
  • What Is Electricity?
  • Conductive Materials
  • The Basic Circuit
  • Amperage
  • Voltage
  • Resistance
  • Ohm’s Law
  • Series Circuits
  • Parallel Circuits
  • Direct Current
  • Alternating Current
  • Wattage
  • Electricity Applications
  • Summary
Class Objectives
  • Identify the fundamental components of electricity.
  • Define and identify conductors.
  • Identify the essential elements to an electrical circuit.
  • Describe the operation of current.
  • Define voltage.
  • Describe the impact of resistance.
  • Use Ohm’s law.
  • Describe a series circuit.
  • Describe a parallel circuit.
  • Define direct current.
  • Define alternating current.
  • Define watts.
  • Describe the relationship between power and electricity.

Class Vocabulary

Vocabulary TermDefinition
alternating current A current formed when electrons flow in one direction, followed by a flow in the opposite direction.
aluminum A silvery white metal that is soft, light, and an effective conductor.
ampere A unit of measurement that indicates the amount of current flowing in a circuit.
atom The smallest distinguishable unit of a material that maintains that material's characteristics.
batteries A device that converts chemical energy into electrical energy. Batteries produce direct current.
circuit A completely enclosed path consisting of various devices that contains an electrical current.
commutator A device used to convert an alternating current into a direct current.
conductor A material that is very effective at conducting electricity. Metals are generally excellent conductors.
control The device that affects or alters the flow of current in a circuit. The control can turn the circuit on or off, or it can perform more sophisticated tasks.
copper A reddish metal that is very ductile, thermally and electrically conductive, and corrosive resistant. Copper is often used to make electrical wire.
current The flow of electricity through a circuit. Current is measured in amperes (or amps).
cycle The time it takes for current to flow, pause, reverse direction, and pause again in an alternating current.
direct current A current formed when electrons flow in one continuous direction.
electricity Energy in the form of a flow of electrons.
electron The smallest part of the atom that revolves around the positively charged nucleus. Electrons have a negative charge, and they are the basic source of electricity.
generator A machine with a rotating component that converts mechanical energy into electrical energy.
hertz A unit of measurement indicating a single cycle in an alternating current.
horsepower A unit of measurement that indicates the amount of electrical power in larger devices. Horsepower is used instead of watts to describe many electric motors.
insulator A material that is highly resistant to the conduction of electricity. Ceramics and polymers are excellent insulators.
kilowatt A unit of electrical power that equals 1,000 watts.
load The device that converts electricity into another form of energy, such as heat, light, or motion. The load uses the current in a circuit to perform work.
milling machine An industrial machine that uses a rotary cutter to remove material from a part supported on its worktable.
ohm A unit of measurement that indicates the amount of resistance in a circuit.
Ohm's Law The law describing the relationship between voltage, amperage, and resistance. Ohm's Law states that volts equals amperes multiplied by ohms.
parallel circuit A circuit that contains multiple loads and multiple paths for the flow of current.
path The part of a circuit that directs the flow of electricity from the source to the load. Copper wire is used as the path in most circuits.
power factor A value used to calculate the correct wattage for a circuit with an alternating current.
proton A particle with a positive charge that is located in the nucleus of an atom.
resistance The opposition to the flow of current in an electrical circuit. Resistance is measured in ohms.
series circuit A circuit that contains multiple loads but only one path for the flow of current.
series-parallel circuit A circuit that contains some loads connected in series and other loads connected to form multiple paths for electricity.
silver A silvery white metal that has the highest electrical conductivity of all metals. Silver is also fairly expensive.
source The device that supplies the current that flows throughout a circuit. Examples of sources include batteries and generators.
volt A unit of measurement that indicates the amount of voltage in a circuit.
voltage The electrical force or pressure that causes current to flow in a circuit. Voltage is measured in volts.
voltage drop The amount of voltage that exists across two points of an electrical circuit.
watt A unit of measurement that indicates the amount of electrical power in a circuit.