العودة الى قاموس المصطلحات

A space completely devoid of matter. In practice, even ultra-high vacuums cannot achieve this but it is possible to reach one trillionth of the amount of the air pressure at sea level in a laboratory. A الفراغ cleaner only usually achieves a 20% reduction in air pressure.

قاموس المصطلحات والتعريف قاموس المصطلحات