Energy conservation and e = mc^2

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Homework Help Overview

The discussion revolves around the relationship between kinetic energy and the equation E=mc², exploring the validity of both equations in the context of energy and mass. Participants are examining the fundamental principles of energy conservation and the definitions involved in these equations.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants are questioning why E=mc² does not include a factor of one-half, as seen in the kinetic energy formula. There is an exploration of the definitions of energy in both equations and how they relate to mass and velocity.

Discussion Status

Some participants have provided clarifications regarding the intrinsic rest energy represented by E=mc² and the specific context in which kinetic energy is defined. There is acknowledgment of the differences between the two forms of energy, but no explicit consensus has been reached.

Contextual Notes

Participants are navigating the distinctions between different types of energy and the implications of velocity in each equation. There is a mention of the derivation of kinetic energy, which may not be fully understood by all participants.

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If Kinetic Energy is mv²/2 how come E=mc² is a valid equation.. wouldn't it have to be divided by two also because c represents a velocity? Thanks for any help.
 
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the equation e = mc^2 is a fundamental relation between mass and energy. A particle of mass m has an "intrinsic rest energy" Eo given by Eo = mc^2

im not 100% on the way that they derived k = 1/2 mv^2 but i do know that its only used when relating mass velocity and kinetic energy.

the Eo is the energy a mass has with no relation to velocity or position. the c is a velocity but its a relation to the speed of light your making, in 1/2 mv^2 the velocity your relating there is that of the particle of mass m.

basically the energies in the 2 equations are not the same, and in one your relating the speed of the mass, and in the other your relating a mass to a constant [the speed of light]

hope that helps.
 
the 1/2mv^2 is derived by integrating the force ma over a certain distance:
[tex] \int_{a}^{b}ma dx[/tex]
 
Last edited:
hey thanks that really cleared things up
 

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