وفر 50٪ من خلال الاشتراك السنوي في مجرة واحصل على تصفح لا محدود لأفضل محتوى عربي على الإنترنت.

اشترك الآن

تمت عملية الاشتراك بنجاح

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عذراً، عذرا،أنت مشترك مسبقاً بالنشرة البريدية

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عذراً، هناك مشكلة في البريد الالكتروني

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get_post_type: string(7) "concept"

التكنولوجيا

سرعة الضوء |  Speed of light

22 أبريل 2020


هي السرعة التي ينتشر بها الضوء في المواد المختلفة، وسرعته في الفراغ ثابتة، وتساوي 299,792,458 متر/ث.