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6

Potentially yes it could. There are no noise-cancelling headphones to stop the U.S. Navy's 235-decibel pressure waves of unbearable pinging and metallic shrieking. At 200 Db, the vibrations can rupture your lungs, and above 210 Db, the lethal noise can bore straight through your brain until it hemorrhages that delicate tissue. If you're not deaf after ...


5

Looks like neutrons can cause visual perception: Visual phenomena noted by human subjects on exposure to neutrons of energies less than 25 million electron volts, Science. 1971 May 21;172(3985):868-70, "Six subjects reported multiple starlike flashes and short streaks on exposure to neutrons of energies up to 25 million electron volts. The probable mechanism ...


5

This is obviously a very broad question, but here are a few thoughts that may be helpful. As dmckee points out in a comment, it's difficult to define consciousness. However, consciousness clearly requires computation, and computation is something that physics can address. There is a psychological arrow of time: we can remember the past but not the future. ...


4

In addition to the deposition location when EnergyNumbers mentions in the comment the types of radiation and the length of the decay chain are an issue. Radon sits at the top of a long sequence of decays many of which are alpha emitting (quality factor $\approx 10$--$20$) including Po-210 (5.34 MeV alpha, yikes!). Also the radon has a non-zero fission ...


3

The RC circuit that approximates a myelinated fiber looks like a series of resistors along the length of the fiber with capacitors connected to ground at the gaps between the Schwann cells. The time to reach discharge voltage at the next junction after depolarization at the prior junctions will be determined by the time it takes to raise the capacitor ...


2

We need to explain a discrepancy amounting to a factor of $10^6$, so clearly the explanation can't lie in things like quality factors for alphas versus betas. Your calculation assumes that exposure due to radon is only due to the air that's in the person's lungs at any given time. But this article says: [...] charged radon particles can easily bind to ...


2

The straight physics answer to this question - namely "Not all physical quantities scale with the same power of linear size." - is perfectly put by Chris White. This essentially answers your question about giant robots - there are no hard limits, but the scaling power issues simply mean that it gets harder and harder to build bigger and bigger. Modern ...


2

This article is very good in describing the dangers of electricity, which I suggest you read. http://www.allaboutcircuits.com/vol_1/chpt_3/4.html To summarise the article, $20\text{ mA}$ for $60\text{ Hz}$ causes "severe pain, difficulty breathing, loss of voluntary muscle control", whereas $20\text{ mA}$ for $10\text{ kHz}$ is in between "threshold of ...


2

Some kinds of mutation provide an example of this kind of indeterminacy. UV light can be bad for our health. One of the reasons is that, when we are exposed to sunlight, UVB photons are absorbed by double bonds in pyrimidines, which break open, become reactive, and dimerize (photo-dimerization). This damages the DNA in the same way that it would damage a ...


2

The universe is made up of one hundred billion galaxies each with between tens of millions of stars to hundreds of trillions of stars. So we have quite a few stars. It used to be somewhat unknown whether or not stars had planets and if so how many. Recently a satellite called Kepler was designed to look for evidence of planets and found that many stars have ...


2

I don't think it's clearly physics, but ... The same shape assumes your head or your hand or ... Circle (sphere) is the most efficient as regards the proportions of the "content" and the "skin". Any other shape requires more protective cover to hold the same amount of "content". And protecting the body from the outside world is the most important function ...


2

The second law of thermodynamics only applies to closed systems. The earth is an open system (as it is continually receiving energy from the sun), hence the 2nd law doesn't apply to evolution and increase in complexity does not violate any laws.


2

This phenomenon is probably related to the cold shock response, a set of physiological changes that come about in response to rapid temperature change, such as that experienced by a human whose face is immersed in a cold fluid. The response is accompanied by respiratory changes, including an initial gasp (see here). It is related to the dive reflex. This ...


1

The repelling is another way of saying that owing to the strength of the hydrogen bonding between water molecules, the water molecules are better off with themselves alone as compared to with non-interacting non-polar molecules within. A substance dissolves only in a solvent, where the solvent-solute interaction is as strong (or stronger) than the ...


1

Schrödinger's work is known for two distinct ideas relating to the nature of living systems. The first is what he called "order from disorder," meaning the way in which organisms can maintain a low entropy (or high free energy) state by increasing the entropy of their environment. (I.e. by eating low-entropy food and excreting high-entropy waste). Although ...


1

The fault in this reasoning comes from the fact that you are inspecting a small part of the system (the biosphere) and ignoring the total entropy in the system. All biological processes, from those present in bacteria (or for multicellular organisms, mitochondria) to firing of neurons in human brains, increase the total entropy of system.



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