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1500 questions
49
votes
5 answers
Why does an egg boiler require more water to cook fewer eggs?
I got an egg boiler machine, on the instructions is stated:
Less water is used when cooking more eggs.
My thermodynamics understanding cannot figure this out yet. Why would I need less water for more eggs?
The machine beeps when the water has…
manuelBetancurt
- 565
49
votes
10 answers
Why are there only four fundamental interactions of nature?
Is there an answer to the question why there are only four fundamental interactions of nature?
Solidification
- 11,483
49
votes
2 answers
What is the possibility of a railgun assisted orbital launch?
Basic facts: The world's deepest mine is 2.4 miles deep. Railguns can acheive a muzzle velocity of a projectile on the order of 7.5 km/s. The Earth's escape velocity is 11.2 km/s.
It seems to me that a railgun style launch device built into a deep…
AdamRedwine
- 4,963
49
votes
6 answers
Does the sea level increase if an iceberg melts?
It was claimed that if an iceberg melts in the ocean, the sea level won't change as the ice displaces as much water as there will be melted water. The other claim was that the sea level should rise because oceans contain salt, so the water in oceans…
Jaakko Seppälä
- 641
49
votes
7 answers
Is the presence of a magnetic field frame-dependent?
I do not have a strong background in physics, so please refrain from using complex mathematics in any answers :)
I was on
this site, and I read:
When an electrical charge is moving or an electric current passes through a wire, a circular magnetic…
Cyclopropane
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49
votes
6 answers
Why is bench pressing your bodyweight harder than doing a pushup?
Why does bench pressing your own bodyweight feel so much harder than doing a push-up?
I have my own theories about the weight being distributed over multiple points (like in a push-up) but would just like to get a definite answer.
mochacat
- 545
49
votes
6 answers
The speed of sound is a single value yet the speed of atoms is distributed over many values. Does the sound wave front smear out?
Sound waves travel with constant speed, but air molecules that transfer action move with different speeds than the ones described by Maxwell distribution.
Why does the sound wave not smear out and dissipate quickly?
UPDATE. It is not just that…
Vashu
- 629
49
votes
1 answer
Why are our planets in the solar system all on the same disc/plane/layer?
I always see pictures of the solar system where our sun is in the middle and the planets surround the sun. All these planets move on orbits on the same layer. Why?
Stephan Schielke
- 965
49
votes
4 answers
Why do some location on Earth have only one tidal maximum per day instead of two?
Most places in the ocean have two high tides and two low tides per "day" (~25 hours). But I remember reading that some locations only have one of each per day.
This answer has some great explanations as well as helpful graphics and links. I'll…
uhoh
- 6,308
49
votes
7 answers
What are gravitational waves made of?
The following facts are what I think I know about gravitational waves:
Distortion of space-time moving away from a source at light speed.
Produced by very powerful event in the universe such as merging black holes.
What I still don't know is what…
user6760
- 12,980
49
votes
2 answers
Cause for spikes in Trinity nuclear bomb test
In Richard Rhodes' book, The Making of the Atomic Bomb, I was reading about the Trinity nuclear test. High speed photos were taken and this one is from <1ms after the detonation. The book mentions the irregular spikes at the bottom of the image, but…
Ryan
- 1,406
49
votes
3 answers
How are classical optics phenomena explained in QED (Snell's law)?
How is the following classical optics phenomenon explained in quantum electrodynamics?
Reflection and Refraction
Are they simply due to photons being absorbed and re-emitted? How do we get to Snell's law, for example, in that case?
Split by…
Sklivvz
- 13,499
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49
votes
5 answers
If a lens focuses all incoming light to a point, how do we get 2D images?
How do lenses produce 2-dimensional images, if a lens bends all incoming rays of light to intersect at the focal point? Shouldn't this produce a single dot of light on a screen placed at the focal length?
This is basically the standard diagram that…
Kristin
- 601
49
votes
5 answers
Do virtual particles actually physically exist?
I have heard virtual particles pop in and out of existence all the time, most notable being the pairs that pop out beside black holes and while one gets pulled away. But wouldn't this actually violate the conservation of energy?
čaritisio
- 593
49
votes
6 answers
What physics paper would a high school student be able to read?
I'm looking for a physics paper which a typical high school student who is new to physics would be able to read and grasp the general idea of the purpose, setup and results, if not the details. To be clear, I don't expect that high school students…
Brionius
- 7,557