Unraveling the Mystery of E=mc2: Speed of Light

In summary, the conversation discusses the equation E=mc2 and the use of the speed of light, represented by "c." The question is asked about which value of c is used in the equation and it is clarified that "c" always refers to the speed of light in a vacuum.
  • #1
ANO94
1
0
i know this might be a dumb question but it was in my head and i would love to hear an answer,

so the famous E=mc2..e obviously energy, m mass, c is the speed of light,
but what speed of light? we all know that c is constant at vacuum but it changes when it goes through another medium like air or glass or whatever it is, so my question was when scientists actually apply this equation...what c do they use? like do they use c of air for example or d they only use the normal c which is 299,792,458 metres per second?
 
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  • #2
"c" always refers to "speed of light in a vacuum"
so there's no confusion here.
 

1. What is the significance of E=mc2 in physics?

E=mc2 is one of the most famous equations in physics and represents the relationship between matter and energy. It shows that energy (E) and mass (m) are interchangeable and can be converted into one another. This equation is important because it helps us understand the fundamental properties of the universe and has been used to develop technologies such as nuclear power and atomic bombs.

2. How does E=mc2 relate to the speed of light?

E=mc2 shows that the speed of light (c) is a fundamental constant in the universe. This means that no matter how fast an object is moving, the speed of light will always remain the same. The equation also shows that the speed of light is the maximum speed that anything in the universe can travel.

3. What experiments have been done to verify E=mc2?

There have been numerous experiments conducted to verify E=mc2, including the famous mass-energy equivalence experiment by Lise Meitner and Otto Frisch in 1938. This experiment involved splitting an atom and measuring the energy released, which confirmed the relationship between mass and energy predicted by E=mc2.

4. Can E=mc2 be applied to everyday life?

While E=mc2 is most commonly associated with nuclear energy and atomic bombs, it can also be applied to everyday life. For example, it explains how the sun produces energy through nuclear fusion and how medical imaging technologies such as PET scans work.

5. Are there any limitations to E=mc2?

While E=mc2 is a fundamental equation in physics, it does have its limitations. It only applies to objects moving at constant speeds and does not take into account the effects of gravity or other external forces. Additionally, it is only applicable in the realm of classical physics and does not fully explain phenomena at the quantum level.

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