Earth – a somewhat bigger laboratory for school Physics

1. Earth – a somewhat bigger laboratory for school Physics Grzegorz Karwasz Andrzej Karbowski Krzysztof Służewski Zakład Dydaktyki Fizyki, Uniwersytet Mikołaja Kopernika w Toruniu http://dydaktyka.fizyka.umk.pl

2. Rationale (I): Polish National Curriculum Base (2007)

3. Rationale (II): XXI Century Science

4. XXI Century Science

5. XIV: Structure and evolution of Earth • Litosphere • Hydroshere • Atmosphere • (Crysphere) • Biosphere XV: Structure and evolution of Solar System

6. Didactical/ heurestic goal • Bring together Physics & Geography • Illustrate, possibly experimentally, phenomena • Choose the minimum knowledge requirements • Make the whole package attractive • Didactical theory context: • neo-realism (show as much as you can, • and even more), • hyper- constructivism (make student construct • his/ her knowledge from apparently nothing, • i.e. pre-existing knowledge in his/her mind) G. Karwasz, Problemy Wczesnego Nauczania, 2013 G. Karwasz, GIREP Conference 2012

7. Case examples: • radioactivity → the age of Earth • two-body mechanics → Earth and Moon • gravity and rotation → shape of Earth • convection and radioactivity → shield tectonics • electromagnetic induction → magnetic field • Coriolis force → general dynamics of atmosphere • Coriolis force → dynamics of oceanic currents • latent heat & convection → tropical storms

8. Three heurestic functions of an interactive/multimedia object • Child: that’s so funny! • Pupil: that’s so easy! • Scientist: that’s so complex! G. Karwasz, J. Kruk, Idee i realizacje dydaktyki interaktywnej, Wyd. Nauk. UMK, 2012

9. Radioactive series • In other words: • a starting point 238U • some „bottle necks” • an ending point 206Pb rad - 1600 lat, gaz radon - 3,8 dnia, polon - 3 minuty, ołów - 27 minut (ten rozpada się przez proces β); bizmut - 20 minut; w kolejnym rozpadzie β powstaje ponownie polon, ale inny izotop, żyjący zaledwie 0,16 milisekundy, itd.

10. What is the age of Earth/Solar system?

11. What is the age of Earth? Science 321, 1828 (2008);Jonathan O'Neil, et al.Neodymium-142 Evidencefor Hadean Mafic Crust Science 309, 576 (2005);M. Boyet, et al.Silicate Earth142Nd Evidence for Early (>4.53 Ga) Global Differentiation of theSilicate Earth

12. What is the age of Universe? Planck mission (March 2013): 13.67 bilion yrs

13. Moon – a companion from (almost) ever http://en.wikipedia.org/wiki/Lunar_eclipse 4.567 bln yrs + ~100 mln yrs ago

14. „Satelite” = body guard G. Karwasz, M. Więcek, Toruński po-ręcznik. Fizyka współczesna, ZDF UMK 2012

15. „Satelite” = orbit stabilizer Physics and Toys → destabilisation of Earth’s axis in 100 mln yrs

16. „Jakiego kształtu jest kula ziemska?”What is the shape of Earth’s ball? Answer: „Geoide” = Earth-like shape Foto: ESA = tautology https://directory.eoportal.org/web/eoportal/satellite-missions/content/-/article/goce

17. Copernicus: Why water does not flow down from Earth’s ball? Także i wody morskie układają się do postaci kulistej [...] jako ląd i woda wspierają się na jednym środku ciężkości Ziemi, który jest zarazem środkiem jej objętości. Newton: Because of gravity remained: „what is the shape of Earth?”

18. Newton: Elipsoid because of the centrifugal force

19. Centrifugal force from textbooks waves of kilometric heights would flush down the globe!

20. Elipsoid is perpendicular to the effective gravity force „flatness” 1/297

21. Parabole is perpendicular to the effective gravity force

22. Springs in mountains flow perpendicularly to iso-height lines In physics we call these lines - equi-potential lines: the gravity force is perpendicular to potential lines

23. Ellipsoid vs. geoid i.e. geometry vs. physics Geoid – constant (gravitational + centrifugal) potential surface

24. GOCE: equipotential lines https://directory.eoportal.org/web/eoportal/satellite-missions/content/-/article/goce

25. Earth’s shape: equipotential surface ± 100 m https://directory.eoportal.org/web/eoportal/satellite-missions/content/-/article/goce

26. Earth’s shape: equipotential surface Geoid is lower than elipsoid in the Himalaya mountains! Potential formula: V=GM/r2 Lower mass → lower r Himalaya are ligth (calcite) rocks

27. What is the shape of Earth? The one, shown by the lever (libella) and this is perpendicular to the vertical Poziomica, pion

28. Earth’s shape: horizontal water because water level is always horizontal, like Copernicus said

29. What is the Earth’s internal structure? S-wave in iron: 3,24 km/s P-wave in iron: 5,95 km/s Sprężyny, stukot

30. What is the Earth’s structure?

31. What is the Earth’s structure? crust ↔ litosphere mantello ↔ astenosphere G. Karwasz, J. Chojnacka, Geografia w Szkole, 2012

32. How old is Europe? M. Grad, T. Tirra, and ESC Working Group, The Moho depth map of the European Plate, Geophys. J. Int. 176 (2009), str. 279.

33. What is the Earth’s crust? Lampa Lava

34. Why this vertical movement? • Heat flux: • 238U: 8 TW (1015 W) • 232Th: 8 TW • 40K: 4 TW • cooling: 20 TW • (electricity production: 10 TW) Physics World, March 2013

35. Quarz, olivine etc. Mg2SiO4 http://webmineral.com/data/Forsterite.shtml#.U6dDmHZcuRM

36. so, the vertical structure is getting complex

37. so, the vertical structure is getting quite complex... Nature09401-f1.2.jpg

38. „Pangea” Geo-fizyka dla nie-fizyków 300 mln yrs ago Justyna ChojnackaZakład Dydaktyki Fizyki Wydział Fizyki, Astronomii i Informatyki Stosowanej

39. and the surface structure? some 500 mln yrs ago

40. Moving continents + 50 mln yrs (?) wosk

41. Colliding continents (I) John Nábelek, et al.Science 325, 1371 (2009); Foto: J. Karwowski, M. Karwasz, M. Visintainer

42. Colliding continents (IIa) Westward: Japan Subduction angle: 45º Dwie kartki papieru

43. Colliding continents (IIb) Eastward: Andes Subduction angle: 15-25º

44. Colliding continents (III) Subduction of oceanic plates Physics World, no 3. (2012) Ryc. K. Konieczna

45. IV Continents drifting away Foto M. Karwasz

46. IVa Continents drifting away Foto M. Karwasz

47. Earth’s magnetic field Dynamo model

48. Magnetic nigthingales

49. Auto-generated electric super-currents →auto-generated magnetic fields Illustration of the dynamo mechanism that creates the Earth's magnetic field 389371aa.eps.2.gif

50. so, it is getting quite complex Glatzmaier and Roberts 1995