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bobie
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If an electron is traveling at C/2, the Lorenz formula says that mass is about 1.15 me, do we get the value of KE simply multiplying 1/2mv2 by 1.15?
Is it as simple as that?
Is it as simple as that?
bobie said:If an electron is traveling at C/2, the Lorenz formula says that mass is about 1.15 me, do we get the value of KE simply multiplying 1/2mv2 by 1.15?
Is it as simple as that?
jartsa said:Relativistic:
KE = 1/2 * changing mass * v^2
bobie said:Thanks, I suppose 1-γ, 0.15, should be multiplied by .511.
jtbell said:No, unless you want to invent a new kind of velocity-dependent "relativistic mass" in addition to the one that everybody knows about but almost no physicists use.
jartsa said:Oh yes, that mass would be the "longitudinal mass" that is proportional to gamma^3, not the relativistic mass, also known as transverse mass, that is proportional to gamma.
(I thought it was the relativistic mass. This time I was so cautious that I checked that longitudinal mass seems to work correctly with the Newtonian kinetic energy formula.)
jartsa said:Oh yes, that mass would be the "longitudinal mass" that is proportional to gamma^3, not the relativistic mass, also known as transverse mass, that is proportional to gamma.
bobie said:Thanks, I suppose 1-γ, 0.15, should be multiplied by .511.
jartsa said:Let's consider following example:
A bike cyclists accelerates from 0 to 0.86 c, while taking good care of his energy balance. (Assistants fire food portions for the cyclist to catch)
Longitudinal mass of the cyclist becomes 8 times larger.
Then there's a short service break. From 0.86 c to 0.87 c the longitudinal mass stays constant.
The change of kinetic energy when velocity goes from 0.86 c to 0.87 c is:
Delta KE = 1/2 * longitudinal mass * (0.87 c)^2 - 1/2 * longitudinal mass * (0.86 c)^2
irrelevantjartsa said:Let's consider following example:
A bike cyclists accelerates from 0 to 0.86 c, while taking good care of his energy balance. (Assistants fire food portions for the cyclist to catch)
irrelevantjartsa said:Longitudinal mass of the cyclist becomes 8 times larger.
uq...
impossiblejartsa said:Then there's a short service break. From 0.86 c to 0.87 c the longitudinal mass stays constant.
jartsa said:The change of kinetic energy when velocity goes from 0.86 c to 0.87 c is:
Delta KE = 1/2 * longitudinal mass * (0.87 c)^2 - 1/2 * longitudinal mass * (0.86 c)^2
PAllen said:irrelevant
irrelevant
impossible
flat out wrong
jartsa said:Excuse me, but it's correct. At speed 0.86 c velocity change is as large as Newton predicts, if we use 8 times more force than what Newton's says to be the correct force for that velocity change. Right?
So eight times more work will be done in this velocity change than what Newton says. E = F*d
jartsa said:Excuse me, but it's correct. At speed 0.86 c velocity change is as large as Newton predicts, if we use 8 times more force than what Newton's says to be the correct force for that velocity change. Right?
So eight times more work will be done in this velocity change than what Newton says. E = F*d
Kinetic energy at C/2 refers to the amount of energy an object has when it is moving at half the speed of light, also known as the speed of light divided by 2. This is a concept in the field of physics and is often used in discussions about the behavior of particles at high speeds.
The formula for calculating kinetic energy at C/2 is E = mc^2/2, where m is the mass of the object and c is the speed of light. This formula is derived from Einstein's famous equation, E=mc^2, and takes into account the effect of an object's mass as it approaches the speed of light.
Kinetic energy at C/2 is a concept that is primarily used in theoretical and experimental physics research. However, it has implications in fields such as particle physics, astrophysics, and cosmology, where the behavior of particles at high speeds is studied.
Since C/2 refers to half the speed of light, which is an incredibly high speed, it is not possible to directly observe or measure kinetic energy at C/2 in real-world scenarios. However, scientists use mathematical models and experiments to study the behavior of particles at these extreme speeds.
As an object approaches C/2, its kinetic energy increases exponentially. This is due to the special theory of relativity, which states that the energy of an object increases as it approaches the speed of light. At C/2, an object would have an infinite amount of kinetic energy, making it impossible to reach this speed.