All Questions
Tagged with speed-of-light mass
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What is a simple example that contradicts the theory that light (photons) could have a super small mass? [duplicate]
The obvious example is that, to bring something that has mass to the speed $c$ requires infinite energy due to special relativity. But what if a kid asked me "What if light/photos had a super ...
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Is a photon truly massless? [duplicate]
First of all, I am not a physicist or mathematician, not even a hobbyist but the following statements have always puzzled me:
$E=mc^2$
A photon is a desecrated particle of energy.
A photon is ...
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Black hole production via light speed [duplicate]
As a test particle with rest mass approaches $c$ relativistic mass increases to infinity, does this mean that the energy required to continue the acceleration will create a black hole (as time also ...
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Lightspeed and Mass=Gravity [duplicate]
As an object approaches the speed of light, its observed mass becomes infinitely large -- Does the Gravity of the object show a corresponding increase and become infinitely large?
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"Pure Energy" in special relativity and why does the rest energy follow from a derivation at the speed of light?
I'm currently studying special relativity by reading through the lecture notes of M. Fowler from the University of Virginia.
The famous equation $E=mc^2$ is derived by analyzing the work done by a ...
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If light had mass
Is there any way to know how fast would light be if it had a mass? Something like 0.000000178536 kg. At least a formula to help estimate it would help, i asked chatgpt and it said ''E = mc²
E = (0....
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1
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What's the speed limit for things with mass?
So the speed limit of the universe is 299 792 458 m/s, but only massless things like photons can archieve this speed. Since things that have mass can reach 99.99999...% speed of light, does that mean ...
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3
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How much mass is needed to make the speed of light equal to 1 mile per second?
The speed of light in special relativity is a constant, 186,000 miles per second, but in general relativity, "the speed of a light wave depends on the strength of the gravitational potential ...
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How to show mathematical equivalence between the idea of relativistic mass and the geometric explanation of why massive objects can't reach $c$?
I've frequently seen two different explanations for why, in SR, it's impossible for an massive object to reach $c$:
As a massive object approaches $c$, its kinetic energy starts being converted to ...
- 2,327
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Finding mass of photon with de Broglie wavelength
The de Broglie wavelength equation is given by:
$$\lambda = \frac{h}{mv}$$
Even though this is used to find the wavelength of the matter (matter waves) , I was curious to find the mass of photon ...
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Relativistic Mass Relative to a Stationary Observer
I know what you’re thinking, “Not another question on Relativistic Mass.” I’ve spent the better part of a day going down the general and special relativity rabbit holes, and I can not find where this ...
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How to measure static mass of light?
I am learning quantum chemistry using a book.
In this book the author deduce
$$p=\frac{h}{\lambda}$$
using three equations below
$$E^2=m_0^2c^4+p^2c^2$$
$$E=\frac{hc}{\lambda}$$
$$m_0=0$$
But how ...
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Does Proca's hypothesis make sense of giving mass to the photon in reference to special relativity?
The Romanian physicist Proca formulated his famous Lagrangian to describe a hypothetical massive photon. From it we derive, as equations of motion, the relations that the electric and magnetic fields ...
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Inertial frame of reference in special relativity
How could we measure rest mass of photon (that would be zero) when we agreed that photon can not be a inertial frame of reference (because of the dominator of Lorentz's transformation)?
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Does local gravity change when approaching the speed of light? (Relativistic mass) [duplicate]
Let's say we'd transform earth into a giant space ship and had some planetary drive that can accelerate it without burning any kind of fuel (so the amount of matter on earth stays the same - we'd ...
