Physics question: since sand in an hourglass exerts more force when it’s flowing downward than it does at rest, will the rising and falling of the wax make the chandelier very slightly wobble? 🤔
this post was submitted on 23 Apr 2026
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That is super interesting about the hourglass. I never considered that, but it makes sense. The sand is transitioning from a higher energy state to a lower one within a gravitational field. Each grain gains momentum during the fall, then exerts that force on the structure when it hits the bottom.
The lava lamps don't start in a stored energy state. They add thermal energy that causes the convection, but the entire time there's a conservation of momentum within the lamps.
It's super cool idea, but I'm pretty sure the chandelier would be stable, not wobbly.
The wax itself moves constantly around the lamp and has mass. Since the frequency this occurs in and the mass within each blob that moves up or down is somewhat random, I would imagine there are times when more mass moves up than down in different parts of the chandelier.
I would expect that it would ever-so-slightly wobble because of that.
Conclusion: we have our opposing theories and an experimental design.
We must test this, for science!
That wax is displacing water. Wax go up, displaced water go down. And they have very similar densities since the movement is so slow. So the net movement of mass is even smaller than what you'd assume.
There is still some movement, more importantly there is some rotational movement as water and wax swap places. So there is some gyroscopic effect exists, stronger than the linear forces.
So if that chain has too little friction (or if it was a string instead of chain) and the chandelier itself not so much mass that will absolutely dominate the lamps, then indeed some really chaotic and even otherworldly wobbling could be seen due to rotational momentum.
But I'm afraid it would be absorbed by the chandelier mass and the friction on the chain.
Yeah they have to have extremely similar densities, such that hot wax floats and cool (but still molten) wax sinks.
It would have to be very slight indeed, since the wax needs to be close to neutrally buoyant in order to rise and fall with the heat currents.
I guess it really depends on the mass difference between the other liquid and the wax. If they're almost the same, there shouldn't be much net force. If they're drastically different you might see some net external force produced. Since the blobs move slowly in the liquid, we have to expect the densities are at least comparable. I'd think the net movement of mass is too.
The water in the lava lamp does the opposite so it balances out.
That only makes this idea better.
When the sand is falling, it's not exerting force. It only exerts force when it hits the bottom. There would probably be a reduction in overall weight when the sand starts falling for a split second, and a corresponding increase as the last few grains hit the bottom. But in the middle, the weight would be more or less constant, give or take random fluctuations.
Not likely enough to be noticeable without special extremely sensitive instruments. The wax has low mass and is moving slowly. The glass container has high mass and is at rest. Mathematically, you could derive how much the lamp moves when a wax blob hits the top of the glass. In practice, it's likely to be negligible.
I'm half way there, and embarrassed! You forgot, I am not cool
very slightly, the weight difference is so miniscule I doubt it'd even look like it were wobbling, and due to other friction in the system may not even register at all.
Judging by these comments: People do know that lava lamps don't have actual lava in them, right?
You never know
If you can see the blobs, it's not lava, if it glows red or white evenly it might be.
Yeah but they do get pretty hot because they have to use incandescent bulbs in order to work. This is basically an ez bake radiator with cool blobs
Macroscopic water-bears
That lamp cord is gonna burn up edit: wrong they only use like a 20w bulb apparently, carry on
My first thought was the power usage as well.
Better idea: like that, but with a ceiling fan instead.
Add LSD to taste
ambiénce
Lavalamptula!
(I know that makes no sense)
Sounds like a thirty year old Final Fantasy spell.
Lavaga!
That's the kind of spell that makes an old wizard croak after casting it.
It made sense to me and I thoroughly enjoyed your exuberance!
That thing would put out a fuck ton of heat.
Atmospheric space heater
real talk: can lava lamps generate electricity from solar power? seems possible bc it moves liquids from heat which maybe could turn a turbine? so then you just need to get the sun to heat the bottom of the lamp and put a turbine in the lamp?
[Chorus]
🎶 I'm gonna swing from the chandelieer
From the chandelieeeeer 🎶
lavalabra!
Lavalampaleire
I want it and 2 tabs of acid. Maybe a third for the wife. Hold the electric bill please.
pretty sure that would only use 120-150 Watt.
Yeah just bulbs. Or Bob Dylan.
" How to keep yourself and five freinds occupied at the dinner party and create a centrepiece that'll leave your guests speechless "
This is the sort of haunt I would want if I had money.
Furniture that looks like it was stitched together in a Homestuck Totem Lathe lol
The glass lava part is fairly easy to remove. I'd be so worried about something knocking those down on somebody's head.
Depends on the maker. The bottles of mine are threaded at the bottom and screw in the base.
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Nice random number generator you've got there.
I'll bet the floor is lava too!
all i see is potential for third-degree burns
Would definitely buy it
I will find a way to burn myself on it. Or one will fall off and splash hot wax globs on me and idk if its water or oil but the less viscous fluid will surely fuck me up too.
I would pay money for that.