Recent content by Debozo

I don't think so. It's the basis of the laws of motion if you think about it Sorry I haven't a clue what you're on about. All I've said is that when something moves it has to move another object in the opposite direction to keep the centre of mass fixed. And there's no way around that. I...

turbo, I think maybe you haven't undestood the question the question is how can any object that isn't firmly anchored to the ground shift it's centre of gravity. The answer is that it can't. If he moves his mass to the right the bike will move to the left. The centre of gravity would stay...

amusing. Ok guys and girls . It's obvious you can't debate the simplest laws of motion without attempting to get get into a kinda amusing condescending personal attack. If what I've said is so obviously wrong, then it should be easy for you to explain why. Nobody here has done so. Nobody here...

Agreed, the flag isn't doing anything much, its just like an old fashioned sream-line (a big one). The pole generates the turbulence and the flag illustrates the flow.

Wrong. Every system (ultimately) is isolated, because ultimately everything is floating in space, just like an astronaut does. In fact if you assume your reference frame is fixed you are contradicting the laws of motion (aka the conservation of momentum). The only system that isn't isolated...

If you use friction/air resistance or whatever to move around (to push against), then you move the planet Earth in the opposite direction. You are on a space-station. A big one. You are stuck on a planet floating in space. But it's not rigidly attached to anything, its just floating like a...

No. It's not possiblle to ever shift the center of mass of any system. If an outside object exerts a force (your external force) then that outside object is by definition a part of the system. And the center of mass of the system stays just were it always was. - until yet some other...

Finally. Somebody with what looks like a sensible answer. Cheers Jeff. Something to think about. I think you've probably cracked it. The higher the rider is, the harder it is for him/her to push against the ground. Probably true. But I don't understand why there's this obsession with...

If he moved the position of the wheels wrt the center of gravity some other mass would move to compensate - other wise the laws of physics are wrong I think the laws say you can't move your center of mass if you can't push against something

No it can't. The bike can not push on the ground until the man has shifted his mass from left to right. And the laws of motion say that it's not possible to shift your centre of mass unless you have something to push against.

OK, a Man on a bike - leans into a corner to make a turn. How does he do that? Don't the laws of physics say that it's impossible for him to shift his center of mass from side to side? There's nothing for him to push against (side to side) It's like being up in space. and he shouldn't be...

I was just trying to keep it simple that's all. Good point you made that direction is very important if the law is going to work at all. They probably realized this for the first time when the law of conservation of momentum was discovered. And the concept of velocity was born. - So I...

russ, if every object in the universe had the same mass, we could easily use the word conservation of speed (well, velocity actually) instead of momentum, and physics would look a lot simpler. Especially to people like me. Unfortunately the objects of mass (atoms) clump together into larger...

Assuming the crash happenened on Earth the motion went into the air molecules and vibrating metal molecules of the cars themselves. It turned into the motion of tiny molecles. That's my question. Is the motion always conserved. If you could add it all up (all the little wobbles of tiny...

Motion is like when something moves, we say that it has 'motion' - it's moving that's all I meant. Alternatively you could say that we see that it's moving and it's going along at a speed of 100 miles per hour. It's definitely moving. The object has motion. Conservation of momentum just...