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1500 questions
39
votes
3 answers
Can the solar system really fit in a thimble?
Almost every time somebody talks about atoms, at some point they mention something like this:
If we remove the spaces between the atoms and atomic components, we can fit the solar system in a thimble.
Or
If we remove the spaces between the…
Adi
- 1,628
39
votes
10 answers
Is Mach's Principle Wrong?
This question was prompted by another question about a paper by Woodward (not mine). IMO Mach's principle
is very problematic (?wrong) thinking. Mach was obviously influenced by Leibniz. Empty space solutions in GR would result in a Minkowski metric…
Gordon
- 4,263
39
votes
9 answers
How can a photon collide with an electron?
Whenever I study the photoelectric effect and the Compton effect, I have always had a question about how a photon can possibly collide with an electron given their unmeasureably small size. Every textbook I've read says that the photo-electrons are…
DH K
- 535
39
votes
4 answers
Why can a flugelhorn easily play its fundamental frequency, when a trumpet can't?
Some Background
I became fascinated with how the overtone series, or harmonics, relates to how brass instruments function. Most trumpet players (or brass, really) should notice that as they play higher notes, they become closer together on the…
fyrepenguin
- 490
39
votes
4 answers
Why most distribution curves are bell shaped? Is there any physical law that leads the curves to take that shape?
All the graphs shown below come from completely different fields of studies and still, they share a similar distribution pattern.
Why most distribution curves Bell Shaped? Is there any physical law that leads the curve to take that shape?
Is there…
Devansh Mittal
- 2,381
39
votes
4 answers
Should a soda bottle be stored horizontally or vertically?
I am having an argument with my friend about how a nearly-full soda bottle should be stored in the fridge, with the goal of keeping the soda from going flat (i.e. keeping as much of the gas dissolved in the liquid as possible). Assume the bottle is…
user25959
- 520
39
votes
4 answers
Why are rain clouds darker?
I was taught in school that clouds are white due to the scattering of light. Since all rays are reflected it appears as white. But I am wondering about rain clouds. Why are rain clouds darker?
user247360
39
votes
6 answers
Vacuum collapse -- why do strong metals implode but glass doesn't?
This question has been puzzling me lately.
I'm sure you've seen demonstrations of metal containers imploding when evacuated. Here, for example, are two videos of vacuum collapse: experiment 1, experiment 2.
However, when the same experiment is…
Akash Chandra
- 409
39
votes
6 answers
Why aren't satellites disintegrated even though they orbit earth within earth's Roche Limits?
I was wondering about the Roche limit and its effects on satellites.
Why aren't artificial satellites ripped apart by gravitational tidal forces of the earth?
I think it's due to the satellites being stronger than rocks?
Is this true?
Also, is the…
Sykhow
- 731
39
votes
1 answer
Why don't merging black holes disprove the no-hair theorem?
The no-hair theorem of black holes says they're completely categorised by their charge and angular momentum and mass.
But imagine two black holes colliding. At some point their event horizons would merge and I imagine the combined event horizon…
user84158
39
votes
4 answers
What is the farthest-away star visible to the naked eye?
My girlfriend and I were watching Cosmos, and something Carl Sagan said got us wondering what the farthest-away visible star is. Obviously "visible to the naked eye" is a fuzzy concept that might have many defensible answers, but hopefully not too…
Micah
- 528
39
votes
14 answers
How could quantum effects occur in the early universe without an observer?
In inflationary cosmology, primordial quantum fluctuations in the process of inflation are considered responsible for the asymmetry and lumpiness of the universe that was shaped. However, according to the Copenhagen interpretation, any random…
Alex L
- 1,145
39
votes
8 answers
Can a battleship float in a tiny amount of water?
Given a battleship, suppose we construct a tub with exactly the same shape as the hull of the battleship, but 3 cm larger. We fill the tub with just enough water to equal the volume of space between the hull and the tub. Now, we very carefully lower…
SlowMagic
- 1,033
39
votes
9 answers
Why do bikes hardly ever skid while braking with the front wheel?
When abruptly braking with the rear wheel on a bike, it tends to skid pretty easily. Doing the same with the front wheel is a very different experience. Instead of skidding, the bike lifts the rear wheel. I've never seen the front wheel of a bike…
Tiago Marinho
- 517
39
votes
12 answers
If gravity disappeared, would Newton's third law make everything that was pressed to the ground by gravity get pushed upwards?
If gravity disappeared, would Newton's third law make everything that was pressed to the ground by gravity get pushed upwards?
Casimir Rönnlöf
- 545