Solenoid
A coil of wire that produces a when flows. With a movable iron core it can pull a plunger, allowing electrical current to operate a mechanical part such as a relay. Reversing or removing the current changes the field; the term describes the coil arrangement, not a protective device.
Using Solenoid in context
Updated
A distinction worth remembering
A solenoid uses a coil to produce a magnetic field, often to move a plunger. The coil’s electrical supply and the mechanical load both matter to its operation.
Questions to take further
- How can I revise Solenoid beyond the definition?
- Explain what Solenoid describes, compare it with a related term and use it in a topic question. State any assumptions and what evidence you would need before applying the idea to real work.
Sources
- OpenStax University Physics: Fields produced by coils — The physical principle used in this comparison; technical installation requirements remain separate.
Where Solenoid fits in the learning path
The Electrical Science section covers these units:
- Circuit Fundamentals
Curriculum mapping: C&G 2365 Units 202/302.
See this section in the full curriculum
This section is on the free path. Lesson availability depends on content review and your learning path.
Read, practise, return
1. Read it in context
- Ohm's LawElectrical Science
2. Try recalling, then explore practice
Use the memory prompt below to connect the vocabulary.
- Electrical Science — quiz previewFree · Electrical Science
3. Return to the meaning
After reading or practising, explain the idea in your own words, then check what you remembered.
Recall a related term
Which term fits this definition? Say it to yourself, then reveal it. This is a memory prompt, with no score or saved result.
A magnet whose field is produced by electric current, often using a coil and an iron core to concentrate the field. Its pull can be switched or changed by changing the current, which is why relays and contactors can use it. It differs from a permanent magnet that keeps its field without a supply.
Electromagnet
Read the Electromagnet entryCompare related terms
Open a meaning to compare its role with Solenoid, or follow its full entry.
Electromagnet
A magnet whose field is produced by electric current, often using a coil and an iron core to concentrate the field. Its pull can be switched or changed by changing the current, which is why relays and contactors can use it. It differs from a permanent magnet that keeps its field without a supply.
Read the Electromagnet entryMagnetic field
The region in which a magnet or current-carrying conductor can exert magnetic force. Drawn field lines show direction and give a visual guide to strength, but they are a model rather than physical wires. Changing magnetic flux through a coil can induce a voltage, linking this idea to motors and transformers.
Read the Magnetic field entryCurrent
Current is the rate at which electric charge flows, measured in amperes (A), often called amps. In a simple closed circuit, the supply drives current through the load and back to the source. Current is not used up by a lamp: energy is transferred there. A cable current rating describes how much current it can carry in stated conditions, not how much it always carries.
Read the Current entryA definition is a start. Using it in a real question is where it sticks.