88 Miles per hour: Difference between revisions
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'''Session 5 – 88 miles per hour''' | '''Session 5 – 88 miles per hour''' | ||
* This session looks at the question of time travel and other topics in the context of why we don’t understand everything. It aims to introduce the concept of modelling and points out how far we have to go to get a complete picture of everything.<br /> | |||
* 88 mph is the speed at which you must go to travel through time in Back to the Future (The trailer shown in the introduction). Are time and space really the same thing – can you Travel in Time? <br /> | |||
* Example - you are asked to guess a number sequence which increases by +2.2 each time. When displayed to zero decimal places, the first 4 numbers follow a regular pattern but then the model that we use (adding just 2) breaks down. Going back to the drawing board often happens in science. One observation can cause a whole theory to be questioned and changed<br /> | |||
* Example from chemistry<br /> | |||
:- Model of atoms as smallest building blocks<br /> | |||
- Model of atoms as smallest building blocks<br /> | :- Plum pudding model<br /> | ||
- Plum pudding model<br /> | :- Understanding of a nucleus (Rutherford)<br /> | ||
- Understanding of a nucleus (Rutherford)<br /> | :- Charged particles in a nucleus<br /> | ||
- Charged particles in a nucleus<br /> | :- Quark model (see session 4)<br /> | ||
- Quark model (see session 4)<br /> | * New evidence and experiments lead to models being refined. It is NOT that the old models are wrong – or that the people who first stated them were stupid – more that new evidence makes a better model possible – however it is still just a model and will no doubt be improved in the future. | ||
* Lord Kelvin made some outlandish statements, but also did some very good science, however it is wrong to consider him stupid for them. Predicting the future is notoriously difficult... <br /> | |||
:http://en.wikipedia.org/wiki/William_Thomson,_1st_Baron_Kelvin<br /> | |||
* Examples | |||
:- Point is demonstrated clearly by the theory of special relativity.<br /> | |||
- Thought experiment – turning the lights on, on a car travelling very | :- Thought experiment – turning the lights on, on a car travelling very, very fast.<br /> | ||
- Is the speed of light in this case c? Or c + v?<br /> | :- Is the speed of light in this case c? Or c + v?<br /> | ||
http://en.wikipedia.org/wiki/Special_relativity<br /> | :- http://en.wikipedia.org/wiki/Special_relativity<br /> | ||
- Mickleson-Morley experiment proved it was always c | :- Mickleson-Morley experiment proved it was always c http://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment<br /> | ||
http://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment<br /> | :- Thought experiment - Light clock – I suggest you only deal with a brief explanation of time dilation and ignore length contraction.<br /> | ||
- Light clock | :- Consequence of this is that as you watch someone move fast you see time slow down for them.<br /> | ||
- Consequence of this is that as you watch someone move fast you see time slow down for them.<br /> | :- Concorde example. Fly 1 clock to JFK and back and leave another @ LHR)<br /> | ||
- Concorde example. | :- Twin example, ignoring the paradox component, a twin visits alpha centauri @ .95c comes back to find her identical twin much older than she is. http://en.wikipedia.org/wiki/Twin_paradox<br /> | ||
- Twin example | :- The case of a black hole<br /> | ||
http://en.wikipedia.org/wiki/Twin_paradox<br /> | * General relativity states that time also slows down in the case of a gravitational field. So time passes faster the weaker gravity is – example the clocks on the GPS satellites have to be constantly corrected. This can lead to extreme slowdowns of time. If you fell into a black hole – your friend watching would see you almost stop completely on the event horizon – whereas you would see all the future of the universe flash before your eyes as you spaghettified. | ||
- | :http://en.wikipedia.org/wiki/Spaghettification | ||
General relativity states that time also slows down in the case of a gravitational field | :http://www.slate.com/id/2199664/ | ||
* Relativity tells us something very strange happens with big and fast things. So what about small things?<br /> | |||
This can lead to extreme slowdowns of time | - Quantum mechanics<br /> | ||
If you fell into a black hole – your friend watching would see you almost stop completely on the event horizon – whereas you would see all the future of the universe flash before your eyes as you spaghettified. | - Key figure Niels Bohr http://en.wikipedia.org/wiki/Niels_Bohr<br /> | ||
- Quantum means “the smallest discrete quantity of some physical property that a system can possess” so a quantum of solace basically means – a very small bit of peace and quiet. It is important because if the universe has a smallest possible size for something – then it will be impossible to measure something smaller.<br /> | |||
- How long is a table? Analogous to the how long is a piece of string http://news.bbc.co.uk/1/hi/sci/tech/8363934.stm<br /> | |||
* Video from the HBO series “the elegant universe” adapted from a book by Brian Greene. The key point is that QM works very very well with the small – and GR works well with the big – but when you deal with something Heavy and small, like a black hole or the “big bang, you get nonsensical answers as you have to use BOTH. Therefore there is something wrong with one or both of these foundational theories in science.<br /> | |||
* Close is often good enough. Video - we got to the moon without worrying about this. | |||
- Key figure Niels Bohr | * But sometimes it isn’t. Video - Chloe and Keith’s Wedding clip is a setup, but it is still funny... <br /> | ||
• Pioneer Anomaly also points to potential wrongness in theory of gravity. http://en.wikipedia.org/wiki/Pioneer_anomaly<br /> | |||
- Quantum means “the smallest discrete quantity of some physical property that a system can possess” so a quantum of solace basically means – a very small bit of peace and quiet. | |||
How long is a table? | |||
Video | |||
Video - Chloe and Keith’s Wedding clip is a setup | |||
• Pioneer Anomaly also points to potential wrongness in theory of gravity. | |||
http://en.wikipedia.org/wiki/Pioneer_anomaly<br /> | |||
End of Session 5<br /> | End of Session 5<br /> | ||
''' | '''Cloudy weather options'''<br /> | ||
• Video task from session 4<br /> | • Video task from session 4<br /> | ||
• Describe in a leaflet to a friend why time isn’t constant!?<br /> | • Describe in a leaflet to a friend why time isn’t constant!?<br /> | ||
• | • Invent your own theory of the universe (you get to name it after yourself)<br /> | ||
Revision as of 08:47, 15 August 2012
'Lesson idea. A presentation about the frontiers of human understanding and the truly strange world proposed by Relativity and Quantum Mechanics. Incidentally, 88 mph is the speed at which the Delorean car is able to travel through time in Back to the Future. This is lesson 5 of 6 in the “Astronomy masterclass” series (SC0018).
Teaching approach. The lesson initially looks at time travel, however the overriding theme is that of modelling(ta) and scientific method(ta). It aims to show students that it is acceptable to get a result that doesn't fit with what you expect. It just means you need to change what you expect next time! (edit)
| Resource details | |
| Title | 88 Miles per hour |
| Topic | [[Topics/Astronomy|Astronomy]] |
| Teaching approach | [[Teaching Approaches/Modelling|Modelling]], [[Teaching Approaches/Scientific method|Scientific method]] |
| Learning Objectives | Students should be able to:
|
| Format / structure | A Narrated Screencast of Session 5 from the Astronomy Masterclass. This fifth session looks at the frontiers of human understanding and the truly strange world proposed by Relativity and Quantum Mechanics. |
| Subject | [[Resources/Science|Science]] |
| Age of students / grade | [[Resources/Secondary|Secondary]]
|
| Related ORBIT Wiki Resources | |
| Files and resources to view and download | For session 5 of the Astronomy Masterclass, see p141 to 199 of the full PDF at https://www.box.com/shared/aqnk3lvr09 STUFF HERE
|
Teacher's Notes
Session 5 – 88 miles per hour
- This session looks at the question of time travel and other topics in the context of why we don’t understand everything. It aims to introduce the concept of modelling and points out how far we have to go to get a complete picture of everything.
- 88 mph is the speed at which you must go to travel through time in Back to the Future (The trailer shown in the introduction). Are time and space really the same thing – can you Travel in Time?
- Example - you are asked to guess a number sequence which increases by +2.2 each time. When displayed to zero decimal places, the first 4 numbers follow a regular pattern but then the model that we use (adding just 2) breaks down. Going back to the drawing board often happens in science. One observation can cause a whole theory to be questioned and changed
- Example from chemistry
- - Model of atoms as smallest building blocks
- - Plum pudding model
- - Understanding of a nucleus (Rutherford)
- - Charged particles in a nucleus
- - Quark model (see session 4)
- New evidence and experiments lead to models being refined. It is NOT that the old models are wrong – or that the people who first stated them were stupid – more that new evidence makes a better model possible – however it is still just a model and will no doubt be improved in the future.
- Lord Kelvin made some outlandish statements, but also did some very good science, however it is wrong to consider him stupid for them. Predicting the future is notoriously difficult...
- Examples
- - Point is demonstrated clearly by the theory of special relativity.
- - Thought experiment – turning the lights on, on a car travelling very, very fast.
- - Is the speed of light in this case c? Or c + v?
- - http://en.wikipedia.org/wiki/Special_relativity
- - Mickleson-Morley experiment proved it was always c http://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment
- - Thought experiment - Light clock – I suggest you only deal with a brief explanation of time dilation and ignore length contraction.
- - Consequence of this is that as you watch someone move fast you see time slow down for them.
- - Concorde example. Fly 1 clock to JFK and back and leave another @ LHR)
- - Twin example, ignoring the paradox component, a twin visits alpha centauri @ .95c comes back to find her identical twin much older than she is. http://en.wikipedia.org/wiki/Twin_paradox
- - The case of a black hole
- General relativity states that time also slows down in the case of a gravitational field. So time passes faster the weaker gravity is – example the clocks on the GPS satellites have to be constantly corrected. This can lead to extreme slowdowns of time. If you fell into a black hole – your friend watching would see you almost stop completely on the event horizon – whereas you would see all the future of the universe flash before your eyes as you spaghettified.
- Relativity tells us something very strange happens with big and fast things. So what about small things?
- Quantum mechanics
- Key figure Niels Bohr http://en.wikipedia.org/wiki/Niels_Bohr
- Quantum means “the smallest discrete quantity of some physical property that a system can possess” so a quantum of solace basically means – a very small bit of peace and quiet. It is important because if the universe has a smallest possible size for something – then it will be impossible to measure something smaller.
- How long is a table? Analogous to the how long is a piece of string http://news.bbc.co.uk/1/hi/sci/tech/8363934.stm
- Video from the HBO series “the elegant universe” adapted from a book by Brian Greene. The key point is that QM works very very well with the small – and GR works well with the big – but when you deal with something Heavy and small, like a black hole or the “big bang, you get nonsensical answers as you have to use BOTH. Therefore there is something wrong with one or both of these foundational theories in science.
- Close is often good enough. Video - we got to the moon without worrying about this.
- But sometimes it isn’t. Video - Chloe and Keith’s Wedding clip is a setup, but it is still funny...
• Pioneer Anomaly also points to potential wrongness in theory of gravity. http://en.wikipedia.org/wiki/Pioneer_anomaly
End of Session 5
Cloudy weather options
• Video task from session 4
• Describe in a leaflet to a friend why time isn’t constant!?
• Invent your own theory of the universe (you get to name it after yourself)
