And in proportion to the number of unanswered questions.
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Split Thread The validity of classical physics (split from: DWFTTW)
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And in proportion to the number of unanswered questions.
Actually, Humber, it means I know what motion relative to a frame of reference is, and you don't.
You also don't know that you don't know.
You also don't know that what you don't know is that you don't know.
But I don't think you are aware of it.....
You also don't know that you don't know.
You also don't know that what you don't know is that you don't know.
But I don't think you are aware of it.....
Rumsfeld?
Did you see the 'hobo in a car video' that was posted in this thread RossFW ? That's 100% of the knowledge you need to understand "frames of reference" in this context.
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Why didn't you look at the video?
Because the treadmill cannot be a "frame of reference" It is a real object not a magic box that can create new "views" or "frames". That is the problem, not the principle of relative motion.
Why do you accept that when you are looking at the cart, you are at windspeed?
I say that's not possible, so I look for errors that tell me so. They are numerous. If I adopt the idea the treadmill is a frame device and test it from that assumption, it also fails. All indicators point to no motion.
A car with a belt spinning its wheels is not like a car in motion. Not at all.
Try to do the same with a boat. Do you think that running a hose over a boat's propeller makes it like it is at sea?
What is the difference between a car on the belt, and a car on four jacks but spinning its wheels?
Real Treadmill
Road = Belt
Wind = Air
Ground = ?
Where is the equivalent of the ground RossFW? If you say it's the belt, then that must mean that the belt is the "equivalent" of the ground; the entire planet. If you say not, but that the belt is the road, then where is ground?
The answer is nowhere, because that place is occupied by the windspeed observer. If you change that, and think of the belt as being similar to the BMW/F1 case, then then (road = belt), (wind = air) and (ground = ground). This means the cart is exactly as you see it. On the belt in front of you, not moving and no windspeed illusion.
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The cart is never on the entire planet. Just the little bit of it under it's wheels at any given time.
It doesn't know if that bit of ground under it's wheels is attached to a treadmill or the earth. It doesn't know if it is not moving wrt the wind around it because both it and the air are still wrt the earth, or moving at the same speed. The forces acting on the cart (I'll give you nebulous differences due to boundary layer, but they will not significantly effect the performance of the cart) are identical in both cases.
You may be able to tell as a distant observer, but as such you have no interaction with the experiment.
I, and every other poster here understand that. It is a simple part of Newtonian physics that says all frames of reference are equally valid.
You don't.
Ziggurat
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Maybe they've got fancy moveable roads where you come from, but where I come from, the roads don't move with respect to the ground.
Did you, I mean did you listen? He first proposes a game. Tell someone in the front seat that you can throw the paper ball faster they can. No matter how hard they try you insist you are faster, right? The assumption is that most people already appreciate that the car's motion does not influence the ball's motion inside the car.
The 'trick' is revealed to be that the car's speed has been taken into account and added to your ball's velocity.
Do you see? The insistence has been that I don't understand what is commonly accepted, in order to make me look stupid, so as to deflect criticism.
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They do at the BMW site, right? Do you think they believe they are moving as fast as Michael Schumacher, when they are observing their treadmill?
I am not sure but have some ideas.
You don't understand any physics at all.
None of you posts make any sense whatsoever.
You use worlds that you don't understand.
About the video. Why do your written nonsense mostly contradict what they talk about in the video if you have seen it and understood it?
So a roller would do? One wheel or four?
Not knowing you are not moving, is not the same as knowing you are moving.
And if you deflect the laminar flow does the car stop?
What experiment. Does it do anything else but sit and spin?
I understand that spinning a car's wheels do not make it move at all, anywhere.
I'll ask you the same questions.
If the car at the BMW/FI site is lifted form the belt with a fork truck. When is it at windspeed? When the wheels are 1cm above the belt, just touching it, or do you have to look away until you are told so?
spacediver
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Humber, here is a real world experiment of firing a bullet out of a moving train.
It's one of those crazy japanese gameshows but it's clear what's going on.
http://www.youtube.com/watch?v=yPHoUbCNPX8
sorry gave the wrong link - this one works
It's one of those crazy japanese gameshows but it's clear what's going on.
http://www.youtube.com/watch?v=yPHoUbCNPX8
sorry gave the wrong link - this one works
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Tell that to Spork. He can't answer my questions either.
Where does it suggest that spinning a car's wheels is the same as moving?
You are making a mountain out of a mole hill. Everybody who as ever been is a car, or train, sees relative motion. Do you expect that it is more difficult to walk one way than the other in a train? But you think I do?
Taken back 400 years so you can "rediscover" the obvious.
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spacediver
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oh the link worked? I thought it was borked - i replaced it with a better youtube link.
This video was meant to demonstrate the idea of relative kinetic energy. Do you see how that relative to the moving truck, the ball has a kinetic energy that is far greater than that relative to someone on the ground?
Yes, just fine. One for each wheel would suffice.
The word "moving" implies velocity. Velociy is relative. It has no meaning unless you specify moving in relationship to what. It can have a velocity relative to anything. That relative velocity is a frame of reference for both objects. All frames of reference are equally valid. Rinse. Repeat....
No, he doesn't.....
ETA:- PREDICTION- NEXT HUMBERISM:- What has that got to do with the cart?
ANSWER:- it nulifies your constant contention that the cart has no KE by pointing out, for the 10000000000000 time, that KE is relative.
we will then be subject to a tirade of meaningless blather...........
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You are telling be something that every baseball player knows. When trying to catch a fast ball, move your hand back with the ball, so as to reduce the impact.
Not bullets. Where does it suggest that you spin a car's wheels, it is like it is moving?
Where does it say that spinning a car's wheels is like it is moving?
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Where does it say that spinning a car's wheels is like it is moving?
ETA1:
Not very likely is it? Where are the vehicles that exploit this idea?
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