insulator
part of speech
noun (an insulator, insulators)
meaning for a pupil
1) An insulator is a material that does not let heat pass through it easily, like wool, plastic foam or air. tree →
2) An insulator is also a material that does not let electricity flow through it, like plastic, rubber, wood or glass. tree →
sense in the lessons
In science lessons, children test materials as good or poor insulators: thermal insulators keep heat in (hot drinks in a flask, a woolly hat, house insulation) or keep heat out (a cool box for ice). Electrical insulators keep us safe: plastic covers on wires and plugs stop electricity reaching our hands. The opposite is a conductor (metals conduct both heat and electricity well). Phrases: «a good insulator», «a poor insulator», «thermal insulator», «electrical insulator».
examples
- Plastic is a good electrical insulator. tree →
- The plastic coating on the wire is an insulator. tree →
- Wool is a good insulator, so it keeps us warm. tree →
- We tested which material was the best insulator for keeping ice from melting. tree →
- Metal is a conductor, not an insulator. tree →
- Air trapped in feathers is a great insulator. tree →
- Polar bears' thick fur and fat are insulators. tree →
- Wooden spoon handles are insulators, so they don't get hot. tree →
note
Countable: «an insulator» (vowel, so «an»). Opposite: «conductor». Verb: «insulate»; noun: «insulation». Myth: a coat does not make heat; it is an insulator that keeps your own body heat in. Water with salts in it can conduct electricity, so wet insulators may be unsafe.
In the corpora
- Wood, plastic, wool, cork and still air are poor conductors of heat, called insulators.
- Insulators also keep cold things cold, like food in a cool box.
- Ice and snow are good insulators and slow down the cooling of whatever is under them.
- Plastic, rubber, wood and glass are insulators.
- Air trapped in wool, feathers or double windows is a good insulator.
Trees and pragmatics
Every meaning and example of «insulator» parsed by Mova, each sentence with its dependency tree and frames.