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28

Your reasoning demonstrates precisely why formal logic alone is insufficient to study nature. In particular, it lacks the ingredient of inductive inference that is a cornerstone of empirical science. A cosmic ray striking the Earth is not some random act of the gods that can have any imaginable consequence whatsoever. It is a cosmic ray striking the Earth. ...


20

"A state of rest" is a relative term. Relative means - measured in comparison to the things around it. When you sit in a train and sip from a cup of coffee, you can do so because the cup is still relative to you even though both of you might be hurtling through the countryside at 200 km/h. For most experiments, objects can be considered "at rest" if they ...


7

For any transformed shape of the Universe, one may always easily define the theory in such a way that its results will be absolutely indistinguishable from the original theory. For example, one may describe the Earth and its vicinity by the polar coordinates $$ R, \theta, \phi $$ so that $R\gt R_E$, the Earth's radius, corresponds to the space outside the ...


5

Revolving around the sun is equivalent to free fall around the sun, so the revolution allows you not to 'feel' the sun's gravity. The rotation of the earth is something that can be measured: (i) a centrifugal force which is a small offset on gravity, and (ii) causes the coriolis force. Both these are small effects, so can often be ignored for laboratory ...


5

The Earth's tilt doesn't change so much as it's position around the sun changes. Notice the North Pole sees more sun in summer than in winter cause it's tilted towards the sun in summer but not in winter. The north pole always points in the same direction into space pretty much. It wobbles slightly, and quite slowly, completing a full wobble every ...


4

Occam suggests that the sounds are either able to be explained as typical noises that 'just happen' or are hoaxes. It is unfortunately extremely common for a large number of copy-cat reports of major "strangenesses" to occur once something suitably notable appears "on the web". There are numerous web discussions about these "phenomena". This 14 minute ...


4

If the electric charge from lightning is captured and harnessed through circuits, eventually it will reach the ground, but once there it will join the general discharge process mentioned by Feynman. It won't lead to any build-up of charge. Incidentally, it would be very difficult to harness lighting with sufficient regularity to make a difference to the ...


3

Just to elaborate on Chris White's point that you can use the same argument to doubt the safety of anything, here's a slight reworking of the argument you give that shows why we should avoid breathing air: So, basically, from those two facts: For [hundreds of thousands] of years [humans have breathed air]. [There are no recorded incidents of ...


3

To a first approximation it would make the longitude of the ground station shift. Assuming the satellites are unaffected by whatever slowed the Earth (ie. tidal forces or seismic activity) But the only way to get a GPS position sufficiently accurate to see the effect would be to use a differential GPS system which compares the incoming satellite signal to ...


2

If someone (like superman) could stop the moon from its orbital motion then yes it would fall towards the Earth. Only then the direction of motion would be parallel to gravity. Same with the I.S.S or the satellites orbiting Earth. They could also spiral in and crash because the atmosphere is taking away their kinetic energy. Just like the comment says ...


2

According to Google the mass of the earth is around $5.972 \times 10^{24}$ kg (presumably that figure includes its 7 billion human inhabitants plus everything else were meant to be sharing with). If we take the average weight for a human as given by WolframAlpha as 62 kg this gives humanity a combined weight of $4.34 \times 10^{11}$ kg - so our share in the ...


2

Yes, see "Measurements of length of day [LOD] using the Global Positioning System" (its persistent Digital Object Identifier is doi:10.1029/96JB01889) and subsequent citing literature. Notice this is not a relativistic effect. LOD is day-averaged measure of Earth's spinning rate, see Wikipedia for background (LOD variations).


2

For any sample of atoms in a gas they have a range of speeds. The likelihood of any atom having any particular speed is given by a probability distribution called the Maxwell-Boltzmann distribution. But the main point is that low mass atoms are more likely to have high speeds. For hydrogen and helium at temperatures typical of Earth's atmosphere there is ...


2

Actually, in a large solar flare particle energies can get up to 1 GeV, but the top energy of some particles is not really the issue. The issue is the flux of these high energy particles. A 10 MeV proton or electron pretty much rips through most spacecraft bodies, thus, their electronics are effectively exposed to particles at these energies. The often ...


2

Neutrinos are produced in the atmosphere all the time as a consequence of cosmic ray interactions, and they mostly then fly right through the planet. So there is no problem with a source. In fact the "flying right through" bit is one of the problems: even the full diameter of a planet simply doesn't intercept a large enough fraction of the beam to make ...


1

"Rest, in physics, refers to an object being stationary relative to a particular frame of reference or another object." - Wikipedia (emphasis mine) While on Earth, the planet is often treated as the default frame of reference. It is not a perfect frame of reference, but for many purposes it is good enough. Since there is no absolute frame of reference, ...


1

Is it the threat of having to eat five servings of fruits and vegetables a day? When the magnetic field deflects charged particles the energy is deflected and this means less radiation and less ionizing radiation from he particles that get deflected. A solar electron, proton, or alpha particle with 10keV would be capable of ionizing molecules and atoms. ...


1

This answer is in order to clarify what the physics is behind the scares for LHC safety and to point out that your statistical analysis is on wrong premisses. High energy cosmic rays permeate the universe, not only planets but all the stars with their order of magnitude greater masses and crossectional areas. If cosmic rays could seed black holes there ...


1

Gravitational force may not need to be continually produced by anything. For example, the Earth is here and it is not produced continually by anything. The same may hold for gravity; it just is there near all the bodies and it is not being produced. Just because we cannot see gravity does not mean it is any less real than the Earth.



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