permanent magnet
permanent magnet — noun
1. a piece of metal or another material that produces its own magnetic field and st
a piece of metal or another material that produces its own magnetic field and stays magnetic for a long time without needing electricity or an outside force to keep its power
The speakers in Sumin’s car contain powerful permanent magnets that produce clear sound.
attributive use: powerful permanent magnets
Hari attached a small permanent magnet to the fridge door to hold up his daughter’s drawing.
common household use: attached to fridge door
Ravindra saw the scrapyard crane drop a car when power failed, but a permanent magnet stuck to a beam.
Marta found the steel screws under the sofa by running a permanent magnet over the carpet.
The recycling plant uses a giant permanent magnet to lift scrap metal onto a conveyor belt.
- hard magnet
technical synonym used in materials science; less common in everyday English
- electromagnet
a magnet that requires electricity to produce a magnetic field
文法句型
permanent magnet + noun (e.g. permanent magnet motor)
adjective + permanent magnet
用法筆記
Countable noun. Often used before another noun as a modifier, as in 'permanent magnet motor' or 'permanent magnet generator'. The opposite concept is an electromagnet, which needs electricity to create a magnetic field.
常見錯誤
❗ 'The magnet is permanent' (when describing a magnet that works). ✅ 'This is a permanent magnet.' — ‘permanent’ describes the type of magnet, not a temporary condition.