Questions in this tag must be answered in a manner that can be understood by a general audience with at most a basic understanding of physics, mathematics and related sciences. Apply it to questions where the asker clearly requests such answers.

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0
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5answers
321 views

What generates such a huge amount of gravitational attraction in a black hole?

I had been fascinated to hear that anything can be swallowed by a black hole. But what causes such a huge amount of gravitational force?
3
votes
2answers
136 views

Colors of light

White light is always said to contain all the different wavelengths of light. Why, then, can we 'make' new colors simply by adding wavelengths? Is it just a matter of our perception, that, when two ...
2
votes
0answers
287 views

What are the basic postulates of string theory? [closed]

I read the Popular Science books, The Brief history of time (Hawking), The fabric of the cosmos (Greene), and The Grand Design (Hawking), etc. but did could not manage to understand what string ...
5
votes
2answers
634 views

Why does a glass breaks when subject to very sharp sound like in opera?

I have seen in Ripleys believe it or not that an opera singer generates a very high frequency of sound and breaks a glass window.How do they do it?
1
vote
1answer
112 views

Age-ing due to Time Dilation

Will a person on top of hill will age faster than one at sea level due to Time Dilation?
5
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5answers
523 views

How to prove that we are living in a 3D world?

Is there any scientific experiment that can lead us to conclude we live in 3 dimensions without the premise of the conception of limited dimensions? Thank you all who helped in the improvement of ...
21
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8answers
2k views

Why is there a size limitation on animals?

Why is there a size limitation on human/animal growth? Assuming the technology exists for man to grow to 200 feet high, it's pretty much a given that the stress on the skeletal structure and joints ...
1
vote
4answers
565 views

Can a wave be two dimensional?

I am having a hard time picturing waves, the image that comes to mind is a bobbing device submerged in still water which generates pulses in all directions (similarly in air). Then how can a wave be ...
-1
votes
1answer
77 views

Mass is a stuff or not? [closed]

Einstein said, there can be no clear definition can be give for moving body mass – instead of giving its name as “rest mass”, it is better to mention, “momentum and energy”. Matter is a stuff, ...
1
vote
1answer
317 views

If time stops for an object, does that object feel gravity?

As far as I understand The GTR, it is said that Mass bends space-time which causes gravity. So every Mass in this universe is flowing through space-time example earth is moving along with space-time ...
0
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0answers
81 views

Neutrons in nucleus

When I asked here why neutrons in nucleus (with protons) don't decay I was told that it would require energy for the neutron to decay, it wouldn't give energy. And since that wasn't really what I ...
10
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8answers
3k views

Is there a proof of existence of time?

It seems to me that there is no such thing as time. There is only movement in the universe and we compare our own movement to a different object to have a sense of time. It can be a clock or a atomic ...
12
votes
4answers
8k views

On a hot day, when it's cooler outside than in; is it better to put a fan in an open window pointing inwards or outwards?

If it's really hot inside, but cooler outside; what is the best way to place a single fan to try and cool a room down? I always assumed it would be better pointing inwards (and this thread suggests ...
35
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5answers
4k views

Is it possible to have a geostationary satellite over the poles?

My understanding of orbital mechanics is very limited, but as I understand geostationary satellite, they stay in place by having an orbital speed corresponding to the spot they're orbiting over. So ...
3
votes
3answers
349 views

Would a sea level rise (on the other side of the Earth) if you would dip your finger into the ocean?

(I'm not a physicist & I hope this question isn't too basic/lame) The question says it all & assuming: No atmosphere No Earth rotation Not a single object in the ocean(s) Ignore all other ...
4
votes
4answers
1k views

Scientist propose solution to quantum measurement problem, explain further

Link to Article The scientists In their recent opus magnum, Theo Nieuwenhuizen (Institute of Physics, UvA) and colleagues claim to have found a solution to the so-called quantum measurement ...
16
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5answers
1k views

String Theory and Standard Model in CERN

I don't know how to say it, but in the TV dominatrices and the popular science books we see the string theory as "the best theory to explain everything", and as "the only game in town"... etc. And ...
7
votes
1answer
202 views

How do ice spikes form?

I recently saw this picture posted on Twitter which shows a so-called ice spike rising from an ice cube tray. I have read the Wikipedia page, but it doesn't mean much to me. My instinct was that it ...
4
votes
4answers
245 views

Basic Question About General Relativity?

I'm a layman that loves Physics. I'm also horrible at math. Having said that I have many, many questions in regards to physics and General Relativity in-particular. I will try to keep my question(s) ...
6
votes
2answers
445 views

Why can't I slap an insect into unconsciousness?

So it is summer, which means I have to deal with insects. Today one has made it into my room and while I tried to work this insect was constantly in my face, which caused me waving my hands in the ...
11
votes
2answers
652 views

Movie airplanes and suction

Having watched a recent action movie (with zombies in it) I wondered whether the suction from a hole in the airplane's hull would really be able to rip out luggage, persons and even seating benches. ...
4
votes
4answers
241 views

Explaining lightyear to non technical people

I need to explain the concept of a light-year to a non technical audience. Actually a presentation about planets and galaxies. It is quite difficult (for them) to comprehend the speed of light itself ...
6
votes
0answers
77 views

Can a submerged place in the sea have huge air pockets? [duplicate]

I know that air can be under water if there is something to contain it that prevents its escape. But can a place such as buildings or ancient ruins submerged totally under water hold air pockets as ...
0
votes
1answer
101 views

how do they rip one single atom from something?

this is simple. what i actually want to ask is, when they do the subatomic particle collision experiments, how do they produce one single subatomic particle, e.g proton, neutron? how do they rip one ...
0
votes
1answer
132 views

At what point does everything become nothing?

I understand that the universe, which I'll call "everything", is expanding and it used to be much smaller. But I keep hearing assertions about a universe coming from nothing. If you rolled the clock ...
2
votes
1answer
96 views

Could one “build” elements?

I was wondering this: would it be possible to "construct" elements by arranging their constituent particles in high-energy environments? So apart from just fusion, could you sub-atomically manufacture ...
13
votes
4answers
1k views

A water pipe from sea level to beyond the atmosphere

If a pipe extended from just above the ocean floor to outside the atmosphere, would water be sucked up it by the vacuum beyond the atmosphere? If a hole was made in the pipe, above sea level, how ...
6
votes
3answers
2k views

Can you make ice red hot?

This video clip allegedly shows an otherwise unspecified ice cube that turns red hot (and burns) due to induction heating. Can somebody explain how this works?
2
votes
1answer
93 views

Moving the endpoints of a wormhole towards each other

Suppose we have a perfectly safe portal/wormhole and we place the two endpoints facing each other so that a person between them would see an endless corridor (with infinite number of herself). What ...
1
vote
2answers
333 views

In which direction do gravitons travel? Do they originate from mass or are they collected by masses?

This is a kind of silly question, that mostly goes unanswered: are gravitons detatched from the objects they act on, like photons in free space. Maybe gravity or gravitons are collected by mass ...
4
votes
0answers
122 views

Physics of Anathem

Disclaimer: I am not asking whether or not the events that occur in Anathem are possible. I understand that this book is a work of speculative science fiction and this site has no interest in it as ...
3
votes
1answer
138 views

physical difference between A and B

We all know that when we say A it sounds different than when we say B. I was wondering what exactly can be the difference between saying A and B in terms of physics. I first thought that it may due ...
4
votes
1answer
547 views

Negative Energy and Wormholes

Apparently to create wormholes you need negative energy/matter. Say you had negative matter/energy, how would it be applied towards making a wormhole?
3
votes
2answers
300 views

Why do some air-conditioned stores blast you with jets of air as you enter?

I went to a grocery store on a hot day that was very well air-conditioned, and I noticed as I went through the open entrance that there seemed to be a very powerful downward air current right at the ...
6
votes
2answers
818 views

Why do objects sometimes fall on their own?

I have observed sometimes that when I keep some objects precariously balanced, for e.g. some objects in a cupboard, they seem quite stable at the time when I place them there but after a certain ...
4
votes
1answer
169 views

Is a singularity a real thing?

I've heard the work a few times now, the most recent in the star trek film. Is a singularity a real thing? If so what is it?
7
votes
1answer
338 views

Antimatter Propulsion System

Is there a possibility ( in theory ) to build a antimatter propulsion system, if so how can we control the collision of matter-anitmatter, will humans be able to control this force just like ...
8
votes
2answers
284 views

Why is the summer, in the temperate latitudes, in average, hotter that the spring?

It is common knowledge that the transition from the Spring to the Summer season occurs in the Summer Solstice when the "Sun reaches its highest excursion relative to the celestial equator on the ...
2
votes
1answer
77 views

Why is the Pegasus launched from a subsonic airplane?

Considering that the reason typically given for launching spacecraft from sea-level as opposed to mountains is that the limiting factor is velocity, not altitude, then why isn't the Pegasus rocket ...
20
votes
4answers
2k views

Is space “real”, or is it some sort of accepted postulate?

sorry for this very naive (layman) question. What is space? It seems to be every where in the equations of physics (as some sort of postulate or hidden hypothesis). We also have a direct experience ...
3
votes
2answers
826 views

Performance of a thermos bottle relative to contents

I'm not a physicist but I majored it at high school (a long time ago) and I study university math. Me and my roommate discussed whether the performance of a Thermos bottle is influenced by how full ...
29
votes
2answers
913 views

What forces are at work causing sand to migrate to the centre of a spinning bucket of water? [duplicate]

A bucket is filled with water and a handful of sand. The water is then spun. Why and what forces are in play which cause the sand particles to congregate in the centre of the bucket?
18
votes
4answers
3k views

Does a car consume more fuel when it's raining?

Yesterday my wife asked me that question, and I couldn't answer. Consider a car, in a sunny day, and that is consumes x gallons per mile. Considering that everything is equal, except that it's ...
6
votes
1answer
173 views

Is there a non-technical way to understand why proving confinement is difficult?

As far as I understand, the basic reason why we are not able to solve QCD at low energies is because it is a strongly coupled quantum field theory, and a part from exceptional situations in simplified ...
134
votes
3answers
40k views

Surviving under water in air bubble

An incredible news story today is about a man who survived for two days at the bottom of the sea (~30 m deep) in a capsized boat, in an air bubble that formed in a corner of the boat. He was ...
0
votes
3answers
1k views

If subatomic particles pop into existence all the time, why don't I gain weight?

Watching Discovery's first episode of the first season of Curiosity (entitled "Did God Create the Universe?" by Stephen Hawking), I heard this information: [...] you enter a world where conjuring ...
-1
votes
1answer
140 views

Why is the Big Bang the biggest explosion in the universe?

What makes the big bang the biggest explosion in the universe? Why even should such an explosion ever happens? Through what process and how does this amount of energy get released as a big bang? Are ...
-4
votes
1answer
207 views

What exactly is implied by Einstein's insight in this scene from the NOVA series “$E=mc^2$ Einstein's Big Idea?” [closed]

In the documentary movie "$E=mc^2$ Einstein's Big Idea?", the narrator says "Einstein had a monumental insight", when Einstein and his close friend were looking at the clock towers in the city. ...
4
votes
1answer
244 views

Quantum field theory quote

I have read this in scientific American: According to quantum field theory, all particles spend a little time as combinations of all other particles" Is this right? How long? And how can they be a ...
0
votes
1answer
2k views

How does gravity effects both time and light if they have no mass [duplicate]

I've been reading about how black holes can effect both time and light with gravity. So I was wondering, doesn't something have to have mass to be effected by gravity? And if so, does this mean both ...