What is E=mc² What is it used for?

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Discussion Overview

The discussion centers around the equation E=mc², exploring its meaning, applications, and the topics it relates to, particularly in the context of physics and energy-mass equivalence. Participants inquire about its uses and seek additional resources for understanding.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant asks for clarification on what E=mc² is and its applications.
  • Another participant provides a link to a Wikipedia page on special relativity for further reading.
  • A participant defines the equation, explaining that it represents energy as mass multiplied by the speed of light squared.
  • It is mentioned that E=mc² is used in nuclear reactions, specifically in the conversion of mass into energy.
  • A participant gives an example involving helium gas, calculating the energy that could theoretically be released if all the mass were converted to energy, illustrating the vast amount of energy involved.
  • There is a note that energy can also be used to create mass, highlighting the bidirectional nature of the mass-energy relationship.

Areas of Agreement / Disagreement

Participants present various interpretations and applications of E=mc², but there is no consensus on a singular understanding or application. The discussion remains open with multiple viewpoints expressed.

Contextual Notes

Some assumptions are made regarding the ideal conditions for mass-energy conversion, and the calculations presented depend on specific definitions of mass and energy. The example provided may not reflect practical scenarios.

Jadaav
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What is E=mc²

What is it used for?

Where can i find more information about it?

it is related to which topic?
 
Physics news on Phys.org


Thanks I'll read it:)
 


Energy= Mass x Speed of Light(squared)
Where C represents the speed of light 299,792,458 metres per second (commonly abbreviated 2.99792458 x 108 )
 


It's used in nuclear reactions, as per the conversion of mass into energy or vice versa.

I believe they can use it to find the energy released when two protons and two neutrons bind to form an alpha particle...
 


Basically, the equation E=mc² is a statement of mass-energy equivalence. Mass is energy, and energy is mass.

Here's an example. Let's say you have a helium balloon of volume 12.4L at standard ambient air temperature and pressure. That volume of helium is equivalent to about 0.002kg of gas.

Now, let's assume (rather unrealistically) that you were able to convert all of the helium in your balloon into energy. How much energy would this be?

Using E = mc², we substitute our known values (mass in kg and the speed of light, c, in meters / second) to obtain a result:

E = (0.002kg)(3.00x10^8)² = approx. 180 TJ (terajoules) of energy.

To help visualize, 1T of TNT yields approx. 4.184GJ of energy. Thus, the helium in your balloon would yield about as much energy as 43kT (kilotonnes) of TNT!

Perhaps even more interestingly, the same can happen in reverse. Energy can be used to create a mass (m) of matter. However, as we have seen here, a great deal of energy is required to generate even a small amount of matter!
 

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