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

مجرة
هارفارد بزنس ريفيو
إم آي تي تكنولوجي
العلوم للعموم
نفسيتي
ستانفورد للابتكار الاجتماعي
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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.


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