Recent content by optics123

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    Undergrad How to Find the Equation of a Plane Through Three Given Points

    plane equation is :ax+by+cz=d we substitute 3 points (0,0,0), (1,1,1) and (2,3,4) in the plane equation, therefore: (0,0,0) -> 0=d (1) (1,1,1) -> a+b+c=d (2) (2,3,4) -> 2a+3b+4c=d (3) by solving equations (1), (2) and (3) relative to a we have: d=0 b=-2a c=a therefore the plane...
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    High School Temperature Definition & Calculation - What is T?

    Hello I can't understand the mean of temperature in general. if it is the average of molecules kinetic energy what is the temperature of almost free space beetween Earth and sun? what is the means of negative temperature? (behind absolute zero) ... "what is the definition of temperature and...
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    High School Which Equation Deserves the Title of the World's Most Beautiful?

    E=mc^2 .