Recent content by peanutaxis

Hi, So when black holes circle each other and eventually collide to form one larger black hole [I believe] that the gravitational potential energy is turned into ripples in spacetime. But that makes me wonder, what if two black holes collided exactly head on? Surely there is a massive amount of...

Hi, If a 1000km space rock called Pluto can meaningfully perturb the orbit of Neptune - which is some 7,800 times more massive - at a distance of no less that 2.4AU, then surely the fact that gravity moves at the speed of light would produce significant effects too(?) Is there any effect, for...

Seems a crazy coincidence that the tiple point of water is also virtually the same temperature at which water freezes/melts. Or is it that the triple point of water was always going to be at the temperature that water freezes/melts (so those two neccessarily co-exist) and then above water there...

Ah, okay. This is at the core of my misunderstanding here I think.

My undesrtanding - which may well be wrong - was that the reason why the speed of causality is the speed of light is because the method by which interactions take place was via virtual and real photons. When in a medium, then, the speed of causality would also be slowed.

Hi, I want to try to solve this puzzle in my head. They say that faster than c travel would break causality. And yet particles can travel through a medium faster than light can in that medium. But surely if that can happen then a particle can arrive at a place faster than information about the...

Yes, I understand that but I am pushing up against this; trying to bend it to try to understand it better. No! Or rather, you have missed the crux of my point - my previous point about 'wrong' frames of reference being without bound. I'm wondering if you can correct me how I am wrong on this...

Hmmmm.🤔 To me - standing stationary on the side watching the real cart - it is ... intuitive that the wind is actually slowed by the propellor which actually transfers energy to the cart. From the frame of the passing wind what ... intuition/reason would there be for the ground to actually give...

Right, so the treadmill scenario is not a good demonstration of the real cart. One is gaining energy from the ground, the other the wind. No, I know physics isn't broken, that was...a purposefully provocative statement in the OP.

Hi. I know this is invalid/wrong because: In the frame of me looking on: Cart = 0, Air = 0. And then suddenly the cart moves. Either the cart gains energy from the treadmill or you have a perpetual motion machine. No way out of that, I'm afraid.

Hi, Like many here I watched Veritasium's awesome videos on this*. And like many I found myself having to drag my mind into understanding why it works. The energy explanation makes the most sense to me. Derek explains that the fan is taking energy out of the existing wind - slowing it down -...

Yes, thanks all.

Just had this pondering: Does the force on a water dam depend merely on the height of the water column behind it or does it depend on the total amount of water behind it? For the same dam if I have a lake behind it that is just a few metres wide vs. having a vastly large lake behind it with the...

Thanks. Yes, I suppose so [puddle].

The bulge at the equator, which Wikipedia says is 42km, means that a point on the equator (at sea level) is 21 km further away from the centre of the Earth than the poles. That's two and a half Everests! I think that the difference in the force of gravity (gravity only) between the equator and...