/sci/ - Science & Math

yesss

dont be stupid thats not going to fly there is nothing keeping the thing from just spinning around in circles opposite of the blades you need some form of stabilization mechanism

>>3169830
>does /sci/ have a sense of humor?

do you have something funny to post?

oh wait... your image is funny because it looks like trollphysics but it isn't, so it's trolling by not trolling

ohlawdydatsumfunnyshit.jpg

good one, OP

>>3169835
It'd be cheaper/better to use Belzona instead of welding.

pic related, its called super metal. Cold welding ftw.

>>3169841
Jerk!

>>3169830
ಠ_ಠ

Somebody should write a physics textbook explaining physical concepts through the gift of troll physics.

Commencing dump of my troll science folder.

>>3171704
Like as a joke, or explaining why <so-and-so> doesn't work?

>>3171735
How strong of a magnet would it actually have to be to achieve this effect? I'm guessing *very* strong

>>3171743
Strong enough for your brain to become full of fuck.

>>3171738
I mean like the one in OP's pic, where you explain real concepts as if it were trolling.

>>3171754
Ceasing dump of troll science folder.

>>3171753
wait, help me out with this one for a minute

>>3171797
In a closed system, entropy increases.
You're shaking it, adding energy to the system, which therefore isn't closed.

>>3171797
I think entropy only applies to chemical changes, not state changes. Plus, there still is constant exchange between the two layers (not visible, but it's happening).

>>3171810
Okay, but what if the only thing in the universe is this jug of oil and water in a gravitational field? At time t = 0, the starting condition is that the oil and water are all mixed up. At a later time, the oil and water will have moved to the ordered state. So the universe's entropy has fallen, no?

The only solution I can think of is that the "ordered" state must strictly have a higher entropy.

>>3171848
How does a jug with oil and water exist without some fundamental laws of physics. These laws will also determine that eventually that jug will turn to dust. Hence entrophy increases.

>>3171864
The universe can have the same laws of physics as ours. That doesn't change the thought experiment.

>eventually

But the 2nd law doesn't just apply on long timescales. Especially for a macroscopic object like a jug of emulsion, it should apply on the nanosecond scale.

>>3171849
I thought of this when I was in primary school.

>>3171993
> mfw I can't figure out what is wrong here

Explain.

>>3169841
Have you ever herped so much that you derped?

>>3171993
Wait what...I don't even what is wrong

>>3171993
> mfw this seems possible

>>3172035
>>3172026
This thing actually works, even though it won't be very efficient. In fact, the already are wave plants out there, just with a completely different design.

>>3171993

lol I troll you

>>3171753

Wait, if we just put it in together and closed it, shouldnt it get mixed together after some time due to entropy ?

>>3172054
Yeah. Entropy inevitably increases in a closed system, when troll guy shakes it, he adds energy and it is therefore not a closed system. Once you let it sit without outside influence, it will mix again.

>>3172056
HA HA, oil and water never mix, entropy fails.

>>3172059
> goes back and checks

Oh shit, we're dealing with oil. Yeah, mind = fucked.

>>3172063
Oil and water don't mix because of gravity. Singe the heavier atoms (water) move down, there's a change in potential gravitational energy. This isn't going to make entropy decrease or something like that.

Cfr. no gravity means that they won't unmix, therefore no decrease in entropy

sure they do. Just superheat them

>>3172056
People ITT seem to forget that there is both entropy increase and energy minimization to consider.

> Explain this bullshit

On a serious note, i know this has something to do with your eyes being used to seeing something, but i want to know why it works when blinking...

>>3173093
Brilliant!

>>3173093
There's more than one cause of image permanence. The image here works because you're actually depleting chemicals in your retina that take time to build back up. The blinking part is internal perception filters that try to produce continuity, coupled with the depleted parts of the retina.

>>3171797
entropy is not "disorder"
it's a real thing, with units and everything

saying entropy is disorder is like saying heat is "bigness" because when you heat up a gas it expands.

>>3173163
Thanks

>>3173201
Heat is actually 2/(3*boltzmann's constant) * average kinetic energy of a molecule

If we're speaking about an ideal gas. It's pretty similar for other gases.

>>3171993
>Tidal power, also called tidal energy, is a form of hydropower that converts the energy of tides into electricity or other useful forms of power.

http://en.wikipedia.org/wiki/Tidal_power

This already exists.

>>3173214

Explain this shit?

>>3171889
can someone tell me why this wont work?
Yeah, I'm dumb

>>3173276
Afterimage.
http://en.wikipedia.org/wiki/Afterimage

>>3173281
It takes force to push the ball in from the bottom (you have to push the water up).

>>3173284
Ah, that makes sense. Thank you.

>>3173281
the force the water makes on the valve, and the valve over the going-downward balloon is greater than the force the underwater ballons make.

>>3173295
aah thank you

>>3171735
You retard, the usa did this in the 1970s, that's why armies use rubber bullets now.

>>3173201
"Disorder" is one of the ways of describing what those units mean.

>>3171797
Entropy always increasing is a bit of an overstatement that many people like to make. A better way to think about it is that systems like to minimize their free energy, which is in a sense a combination of their internal energy and their entropy. In the case of an oil/water mixture there is an energy cost associated with mixing the molecules since water is polar and likes to mix with itself (or other polar molecules), allowing the mixture to reduce its internal energy at a relatively small entropy cost. If you increase the temperature then the entropy-like term becomes larger so that a more stable state may include more mixing. Physically, the increased thermal excitation of the molecules pays the energy cost of mixing, by allowing the oil molecules to obstruct the intermolecular bonds between the water molecules. This is why cocoa powder (or whey powder if you're a fag) doesn't mix with your milk when its cold, but does when it's hot.

>>3171752

That's really cool how chemistry does that. What allows H20 to act so differently from its components?

Sweet mother of god I love how culture mutates in mediums like 4chan, bravo OP

>>3173201
Strawman agrument.
more entropy == more disorder
more heat =/= more biggness
e.g. water

>>3171884
wait, this is possible right? as long as the rope is long enough?

>>3173315
>more stable state

More probable macrostate, rather. It's a while since I did any thermal physics, I keep thinking in terms of quantum physics.

>>3173345
It's a space elevator. You need sufficient tensile strength and a counterweight (the ship, I suppose).
http://en.wikipedia.org/wiki/Space_elevator

>>3173345
>as long as the rope is strong enough?

Fixed that for you. Space elevators are a pretty old idea, but there still isn't a material with the required physical and chemical properties.

>>3173352
woh okay, thanks

>>3171858
>>3171884
I think nasa tried this with STS 76

>>3173428
You would have to be in geostationary orbit, which is 10x higher than the space shuttle can go.