What is the initial kinetic energy of a point charge traveling at velocity v?

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The discussion centers on calculating the initial kinetic energy of a point charge traveling at velocity v, acknowledging that energy is radiated during acceleration as described by Larmor's formula. The initial kinetic energy is questioned, particularly how to represent it numerically, especially when considering deceleration and energy loss. While traditional kinetic energy is expressed as E=1/2mv^2, the conversation highlights that at relativistic speeds, kinetic energy is better defined as the difference between total energy (mc^2) and rest energy (m0c^2). The relationship between charge and kinetic energy is also emphasized, suggesting that for charged particles like electrons, charge and velocity may be more relevant than mass alone. Ultimately, understanding kinetic energy in the context of both charge and relativistic effects is crucial.
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I understand that when a point charge accelerates that it radiates energy due to the acceleration field. Larmor's formula shows the power which is radiated, and is written: P=uoq^2a^2/6(pi)c. My question is this. How can you calculate the initial kinetic energy of a point charge which is traveling at a velocity v? I understand that if the point charge is decelerating until it reaches v=0 then its kinetic energy will be less because it radiated energy away while accelerating. But I am just not sure how to numerically represent the total kinetic energy of the particle prior to decelerating. Is it just E= 1/2qv^2?
 
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Kinetic energy for particles going at ordinary speeds is m0v2/2.

However, when getting close to the speed of light, the kinetic energy is the difference between the total energy and the rest energy. The total energy is mc2 while the rest energy is m0c2. m=m0/sqrt(1-(v/c)2).
 
Isn't 1/2mv^2=gravitational kinetic energy? If talking about the kinetic energy of an electron, wouldn't it be more accurate to talk of kinetic energy in terms of charge and velocity since charge is what causes the electric force?
 
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