Two more physics things....
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OriginalGriff wrote:
Head on: it's my inertia that will affect the damage to me, not the inertia of the other vehicle.
Are you sure? Two identical cars head on will stop dead in a mangled mess, but if the other car happens to be bicycle despite you having the same inertia I would assess your chances would be better than the bike's.
Regards, Rob Philpott.
Indeed, but since the choice was "a head-on collision with another car when both doing 40, or plough into a stationary car at 80mph" it's pretty clear which I would prefer. If the choice was a stationary car at 80, or my little car and a 40-tonne lorry with us both doing 40, then my choice would be quite different! :laugh:
The universe is composed of electrons, neutrons, protons and......morons. (ThePhantomUpvoter)
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In terms of the first one, I tend to agree but the picky go into what's dissolved in the water. Icebergs I understand tend to be fresh water whereas lakes do not and as such their densities are slightly different. Or something.
Regards, Rob Philpott.
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An iceberg melts on a lake. Does the water go up, down or stay the same? The energy of a moving object goes up squared to its speed (half MV squared). So, travelling at 80mph you have 4 times the energy than at 40mph. With this in mind, would you rather be on a head-on collision with another car when both doing 40, or plough into a stationary car at 80mph? Edit These are well debated things in the pub and as such I do not have definitive answers, although I have my own beliefs.
Regards, Rob Philpott.
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An iceberg melts on a lake. Does the water go up, down or stay the same? The energy of a moving object goes up squared to its speed (half MV squared). So, travelling at 80mph you have 4 times the energy than at 40mph. With this in mind, would you rather be on a head-on collision with another car when both doing 40, or plough into a stationary car at 80mph? Edit These are well debated things in the pub and as such I do not have definitive answers, although I have my own beliefs.
Regards, Rob Philpott.
The car one is complicated as to whether the brakes in the stationary car are on. If the brakes are off, then both cars end up moving at 40 (conservation of momentum) and so the energy lost in the collision is the same in both cases. If the brakes are on then the energy dissipated (and shared on the occupants) is higher in the stationary car case. The usual example is the choice of stopping dead by running into an identical car at 40, or stopping dead by running into a brick wall at 80, here the brick wall case has 2x the energy to wreak destruction.
Peter "Until the invention of the computer, the machine gun was the device that enabled humans to make the most mistakes in the smallest amount of time."
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An iceberg melts on a lake. Does the water go up, down or stay the same? The energy of a moving object goes up squared to its speed (half MV squared). So, travelling at 80mph you have 4 times the energy than at 40mph. With this in mind, would you rather be on a head-on collision with another car when both doing 40, or plough into a stationary car at 80mph? Edit These are well debated things in the pub and as such I do not have definitive answers, although I have my own beliefs.
Regards, Rob Philpott.
Iceberg question: Depends in how much of iceberg was underwater and how much was in air. Reason being, ice will have more volume than water for same mass. So, iceberg after melting will result in reduced volume. If iceberg displaced say 1000 m3 of water and after melting resulted in 1000 m3 of water water level remains same. But if there was enough iceberg above water level to result in more volume of water after melting, water level will rise. I have ignored evaporation or any other condensation, anything drinking/stealing water, drooling fishes, people throwing garbage in the lake during the process and any other reason that renders my theory as invalid.
"Bastards encourage idiots to use Oracle Forms, Web Forms, Access and a number of other dinky web publishing tolls.", Mycroft Holmes[^]
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a) Mass displacement. The volume of water displaced by the ice is same as the mass of the water in the ice. It remains constant. (Ever heard of Archimedes? He was an ancient Greek Gymnophile Sprinter) b) Crash at 40 into a moving car. (This is actually based on design engineering of modern cars rather than the rather boring physics of it all).
--------------------------------- I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC Link[^]
If i'm not mistaken, water is one of the few liquids that expands when going solid (ice). This is due to the crystallization. That means that water takes up LESS space then ice and thus the water level should drop. Ah, if only it was that easy; ice bergs tend to be 1/7 above water and 6/7 submerged, so you need to add the non-submerged ice volume (when melted). So it all depends on the expanded level of the ice. (which I don't know) ;P
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Iceberg question: Depends in how much of iceberg was underwater and how much was in air. Reason being, ice will have more volume than water for same mass. So, iceberg after melting will result in reduced volume. If iceberg displaced say 1000 m3 of water and after melting resulted in 1000 m3 of water water level remains same. But if there was enough iceberg above water level to result in more volume of water after melting, water level will rise. I have ignored evaporation or any other condensation, anything drinking/stealing water, drooling fishes, people throwing garbage in the lake during the process and any other reason that renders my theory as invalid.
"Bastards encourage idiots to use Oracle Forms, Web Forms, Access and a number of other dinky web publishing tolls.", Mycroft Holmes[^]
d@nish wrote:
Depends in how much of iceberg was underwater and how much was in air.
About 1/7 in the air and 6/7 submerged, if I'm not mistaken :thumbsup:
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I'm sure there's a boring definition out there - but isn't the dead sea well, a sea not a lake?
MVVM# - See how I did MVVM my way ___________________________________________ Man, you're a god. - walterhevedeich 26/05/2011 .\\axxx (That's an 'M')
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An iceberg melts on a lake. Does the water go up, down or stay the same? The energy of a moving object goes up squared to its speed (half MV squared). So, travelling at 80mph you have 4 times the energy than at 40mph. With this in mind, would you rather be on a head-on collision with another car when both doing 40, or plough into a stationary car at 80mph? Edit These are well debated things in the pub and as such I do not have definitive answers, although I have my own beliefs.
Regards, Rob Philpott.
If it's a more or less natural iceberg and a freshwater lake, then the level should remain the same as an iceberg is more or less fresh water (I believe, I haven't licked one recently) so plain old Archimedes has the math
MVVM# - See how I did MVVM my way ___________________________________________ Man, you're a god. - walterhevedeich 26/05/2011 .\\axxx (That's an 'M')
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I'm sure there's a boring definition out there - but isn't the dead sea well, a sea not a lake?
MVVM# - See how I did MVVM my way ___________________________________________ Man, you're a god. - walterhevedeich 26/05/2011 .\\axxx (That's an 'M')
No, it is an endorheic lake. It is not linked to the oceans and water is only lost through evaporation. (Aral Sea and Caspian Sea are both lakes too).
--------------------------------- I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC Link[^]
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No, it is an endorheic lake. It is not linked to the oceans and water is only lost through evaporation. (Aral Sea and Caspian Sea are both lakes too).
--------------------------------- I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC Link[^]
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The level stays the same: When ice is submerged in water, being of lower density than the water it displaces the upthrust created on the ice by water is equal to the weight of the displaced water. When the ice melts its volume decreases (as it's density increases) but its weight remains the same and remains equal to the weight of displaced water when the ice was frozen. Head on: it's my inertia that will affect the damage to me, not the inertia of the other vehicle.
The universe is composed of electrons, neutrons, protons and......morons. (ThePhantomUpvoter)
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No, it is an endorheic lake. It is not linked to the oceans and water is only lost through evaporation. (Aral Sea and Caspian Sea are both lakes too).
--------------------------------- I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC Link[^]
According to the fount of all buman knowledge A sea is a large body of saline water that may be connected with an ocean or may be a large saline lake that, like the Caspian Sea, lacks a natural outlet. Sometimes the terms sea and ocean are used synonymously.[1]
MVVM# - See how I did MVVM my way ___________________________________________ Man, you're a god. - walterhevedeich 26/05/2011 .\\axxx (That's an 'M')
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According to the fount of all buman knowledge A sea is a large body of saline water that may be connected with an ocean or may be a large saline lake that, like the Caspian Sea, lacks a natural outlet. Sometimes the terms sea and ocean are used synonymously.[1]
MVVM# - See how I did MVVM my way ___________________________________________ Man, you're a god. - walterhevedeich 26/05/2011 .\\axxx (That's an 'M')
The same standard repository of all knowledge and wisdom defines the Dead Sea as "...the deepest hypersaline lake in the world" Sea Hear[^]
--------------------------------- I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC Link[^]
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The same standard repository of all knowledge and wisdom defines the Dead Sea as "...the deepest hypersaline lake in the world" Sea Hear[^]
--------------------------------- I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave CCC Link[^]
Just goes to show that you can't believe everything you read on the interwebs
MVVM# - See how I did MVVM my way ___________________________________________ Man, you're a god. - walterhevedeich 26/05/2011 .\\axxx (That's an 'M')
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Just goes to show that you can't believe everything you read on the interwebs
MVVM# - See how I did MVVM my way ___________________________________________ Man, you're a god. - walterhevedeich 26/05/2011 .\\axxx (That's an 'M')
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Hmmm. Not sure of the veracity of that instruction!
MVVM# - See how I did MVVM my way ___________________________________________ Man, you're a god. - walterhevedeich 26/05/2011 .\\axxx (That's an 'M')
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No that's Southend on Sea. I'm assuming you mean culturally :-D
"The secret of happiness is freedom, and the secret of freedom, courage." Thucydides (B.C. 460-400)
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No that's Southend on Sea. I'm assuming you mean culturally :-D
"The secret of happiness is freedom, and the secret of freedom, courage." Thucydides (B.C. 460-400)
