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0
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1answer
129 views

What is the strength of the magnetic field required to penetrate an average human body?

Introduction Suppose you are an experimental nanobot researcher trial-ling a new form of medication that involves activation and control of nanobots within the cells of the interior of the human body ...
0
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0answers
28 views

What amount of force could be created by a person “swimming” in air?

Had a question on a physics test, a person is at rest on a frictionless surface and can not throw anything, can they move? I said yes, by "swimming" against the air and got docked because "it ...
0
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3answers
77 views

Lifting and putting down a weight

A man in a gym lifts a weight and then puts it down where it was before. 1) What can be say about the work done by the man to the weight? 2) Can it be equal in absolute value to the work made by ...
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0answers
16 views

Bimolecular and Isomerization reactions

Is it possible to describe a reaction of the $$ A+B \rightleftharpoons AB $$ exactly using the solution of an isomerization reaction? $$A \rightleftharpoons B$$ I just can not figure it out the ...
-4
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2answers
83 views

Do animals defy gravity? [closed]

I am a beginner and trying to understand the concept of gravity Do animals defy gravity? If yes, which animal defies and in what way it does? Sorry had I asked something wrong
0
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0answers
48 views

Deriving an upper limit to the information in a human brain

For this question I am presuming that the human brain works deterministically and all information in a human brain is, once you get down to the lowest level, stored through the arrangement and other ...
-1
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2answers
448 views

Space-time hospitality

Are there any reasons to assume that organic processes cannot arise in relatively flat spacetime environments? An argument for the existence of a critial value or window.
0
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0answers
15 views

What material used in soil based microbial fuel?

I have seen from wikipedia that there are soil based microbial fuel which need only anode and cathode while soil itself could act as proton exchange filter But what kind of other material it needed? ...
2
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0answers
40 views

Stability of plants and buildings: the role of the xylem

Dicotyledon plants show a stem structure with many xylem tubes, hollow but with lignified (woody) walls. These are arranged as in the figure below, in a circle. Their roots, on the other hand, have ...
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3answers
154 views

How much energy does it take to simply run forward?

I'm interested in tracking as much data about my runs as I can in an effort to get faster, and while I can easily estimate energy expenditure during an uphill run due to the change in elevation, I ...
3
votes
1answer
84 views

Neutrinos and DNA

This is a question which bridges the gap between biology and physics... but I thought this was the best place to ask it. I remember reading a while ago that it is thought that neutrinos may play a ...
47
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3answers
20k views

Why don't electric fish shock themselves?

Fish like electric eels and torpedoes have specially designed nerve cells that allow them to discharge hundreds of volts of electricity. Now, while pure water is usually nonconductive, the dissolved ...
1
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0answers
61 views

A leaf-cutter ant can lift 50 times its own weight. Can a human-sized ant lift a baby blue whale? [closed]

I found this statement/fun game in a nearby insect zoo: It says that as leaf cutter ant can lift 50 times its own weight, if you're 120 pounds and as strong as an ant, you could lift a baby blue ...
7
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1answer
5k views

How much sky do we see at any one moment?

When we look at any particular point the sky, what percentage of the celestial sphere do we see? This question arises from the notion that on average there passes one meteor per hour overhead. So ...
6
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2answers
787 views

How many frames can human eye see? [closed]

What's the limitation of our eyes? Can we differentiate 60fps from 120fps? Are new 144hz monitors just a marketing trick? Couldn't find any proper journals or studies about the matter.
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2answers
42k views

Effects of a very large magnetic field on the human body

Ever since reading about the NHMFL I have always wondered about this and asked several people without getting a good satisfactory answer. My question is, considering the simplest case let's say a ...
2
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0answers
94 views

What is the maximum magnetic field that a human body can withstand? [closed]

Are there limits to the exposure of human bodies to magnetic fields? What happens if we cross that limit? How to create such magnetic fields? Has this been tried out?
-2
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1answer
323 views

Time dilation and biological changes

I have watched the movie Interstellar and like most of the people who watch it, I was intrigued by the effects of time travel on the astronauts. After reading some articles and watching some videos, I ...
0
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0answers
20 views

Hiccup in frequency domain

Main question: What would the Fourier transform of hiccup look like? This question is too general so let me elaborate a few possible approaches. Hiccup just as a series of pulses (of no matter what ...
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0answers
46 views

Quantum beats and Quantum mechanical side of photosynthesis

I have two questions. One concerning quantum beats alone, another - process of photosynthesis. I am very well aware that there is strong evidence suggesting that mechanism that leads light through, ...
1
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1answer
97 views

How much work can the human body do before dying of exhaustion [closed]

If we could assume: We don't increase our energy from absorbing food. Our human example in scope isn't starving or suffering from malnutrition. I mean how much work can we do until the body would ...
0
votes
1answer
356 views

Are muscle cells electric dipoles?

I'm wondering how we can detect the electrical activity of a muscle cell. My initial thought on this question was that the membrane potential, around $\Delta V_{\text{membrane}} = -80mV$ across the ...
0
votes
1answer
80 views

What is the real definition of entropy? [duplicate]

In our bio class our teacher told us that entropy was the amount of heat lost by a system. But I had learned before that entropy was like chaos / disorder in a closed system. Which definition Is ...
-2
votes
1answer
52 views

Is it true Mars once had life? (like Earth) [closed]

Nasa had proven Mars once had water and still has under ground. So dose that mean mars once had life or maybe still has?
2
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1answer
51 views

Suffocation in a granular medium

I read of a recent accident in Alberta in which three girls fell into an open bed truck carrying canola seeds and suffocated. In that situation would it have been possible to keep breathing by using ...
0
votes
1answer
42 views

Properties of infrasound of our muscles?

I have read, that some animals (like cats) are able to hear other animals (like humans) staying still by percepting infrasound, emmited by their muscles. Is this true? I know, muscles are really ...
93
votes
16answers
176k views

How does mass leave the body when you lose weight?

When your body burns calories and you lose weight, obviously mass is leaving your body. In what form does it leave? In other words, what is the physical process by which the body loses weight when ...
1
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1answer
47 views

What is the atomic composition of the human body, by volume?

According to Wikipedia, the composition (by atomic percent) of the human body is: 62% hydrogen 24% oxygen 12% carbon 1% nitrogen etc. Question: What is our volumetric composition*? *I get this is ...
1
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0answers
66 views

Effects of light wavelength on the Hamiltonian of the FMO complex

Recently, I have been interested in the energy transfer within the FMO complex. I was wondering, how could the wavelength of the light that excites the complex affect the energy transfer efficiency. ...
2
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3answers
3k views

Could submarine SONAR kill a diver?

Could a diver swimming next to a submarine be killed or seriously injured by its SONAR? What physical aspect of SONAR affects the human body in a potential harmful way?
0
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0answers
62 views

Is it true that whenever any non rigid body moves, there must be a delay between the ends? [duplicate]

Very sorry if this is still considered a duplicate to this, but unfortunately the answer to this question cannot address this because mine is a nonrigid body and involve biological locomotion concepts ...
2
votes
1answer
67 views

Biological heat dissipation methods

If the human body is facing temperatures above it's own temperature in a humid environment eg. a rainy jungle above 37 degree celsius, are there any mechanisms that still allows heat dissipation? I ...
17
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6answers
2k views

Physics of how the cochlea isolates frequencies along its length?

Can anyone explain the separation of frequencies along the basilar membrane of the cochlea please? (equations would be nice) I understand it being related to the resistance caused by fluid in the ...
0
votes
0answers
43 views

Magnification: Microscopes Telescopes

What is the difference between the way a microscope magnifies say a star and a telescope say a cell? Why is it, that the eyepiece of a telescope magnifies stronger when it is smaller and with a ...
0
votes
2answers
552 views

Why bumble bee cannot fly aerodynamically? [duplicate]

I just saw this pic So I got curious and logged in on physics.stack first time, is it true? I am a math major and usually wander on mathstack but I would like to understand why Bumble bee cannot ...
2
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4answers
1k views

How does the introduction of living things into a closed system affect the rate of change of entropy?

Does the introduction of living things into a closed system increase or decrease the overall rate of change of entropy of a system?
0
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1answer
128 views

What happens when a bird lands on a power line?

I know that when a bird is sitting on a high-voltage power line, virtually no current flows through the bird because there is (almost) no voltage drop between its legs, the two points are ...
-2
votes
3answers
157 views

If radiation didn't exist, would everything live longer? [closed]

I recently noticed that dying of old age is similar to a death by radiation - hair loss, weakened immune system etc. and I was wondering - Does background radiation limit our lifespan, or that of any ...
0
votes
2answers
100 views

Why do corpses come back to water surfaces after sinking at first?

I want to know that why do dead bodies or corpses come back to the water surface after being sunk at first by the use of stones or anything. For what I can understand, I think it's due to water ...
1
vote
1answer
32 views

When I put 2 electrodes into a electrical conductive solution, does the volume of the solution around the electrodes have biological effect?

Media these days give me a common sense that it is able to hurt someone if they step on a wet floor with a electric cord dipped in, several movies have this scene.However, I wonder if I set up an ...
7
votes
1answer
2k views

Would travelling at relativistic speeds have any impact on human biology?

If a person was sitting on a craft that has accelerated to near light speed speed from Earth (e.g. 99.999% of light speed) would there be any impact on his or her human biology due to relativistic ...
7
votes
3answers
1k views

Most True to Life Physics & Biology Simulation Engine? [closed]

I'm a programmer. I code in C++, C#, HTML5, and PHP. There are many graphics engines I have at my disposal. The question is: Does there exist a graphics engine that is as true to our reality as ...
-5
votes
1answer
72 views

What is the top speed of the SR-72 aircraft? What affects would traveling at this speed have on the human body? [closed]

What is the top speed of the SR-72 aircraft? What affects would traveling at this speed have on the human body?
2
votes
0answers
75 views

Insect Eyes Vs Human Eyes?

Humans have frontal eyes. Less field of view. But better resolving power. Insects have lateral eyes. This means they have a large field of view. In some female insects the lateral eyes have much more ...
2
votes
0answers
120 views

What biology knowledge can be applied in physics? [closed]

After asking a commensurate question in Biology.SE (What physics knowledge can be applied to biology of organisms and ecosystems?), I wonder about the reverse direction: What biology knowledge can be ...
2
votes
1answer
248 views

Would a six-inch person face certain death when falling from a great height?

In Mary Norton's The Borrowers Aloft, the borrowers are like humans in every way except size - normal adult height is six inches. One family of three is captured by a human couple and housed in an ...
2
votes
1answer
94 views

What is the physical clock ticking inside a living cell? [closed]

What is the physical process which determines the timescale of the aging of a living cell? It might be that on the macroscopic scale, i.e., aging of the human, the gravitational force is one factor ...
1
vote
1answer
46 views

How big are soluted salts in drinking water?

I have just seen the TED talk Michael Pritchard: How to make filthy water drinkable where a device called LifeSaver bottle that filters particles that are bigger than 15nm out of water. I have heard ...
21
votes
9answers
3k views

Why can we cycle faster than we can run? [duplicate]

This seems obvious: faster long-distance runners hit ~20 km/h (marathon records) while fastest cyclists can do ~40 km/h (Tour de France stats). But on the physical/biological level this doesn't seem ...
1
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0answers
44 views

dose physics affectthe biological like this [closed]

According to neural sciences the brain process information and reacts in 1 teen of a seconds the numbers add up to be 10.596674 loest is 30 to 20 years the course of time in reality recorded by our ...