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3. Demonstration of an optical technique that allows us to see small changes in the index of refraction in air. A point source of light is reflected from a concave mirror and focused onto the edge of a razor blade, which is mounted in front of the camera. Light refracted near the mirror and intercepted by the blade gives the illusion of a shadow.
Seen here are the heated gases from a candle flame and a hair dryer, helium gas, and sulfur hexafluoride gas.
4. https://www.ted.com/talks/honor_harger_a_history_of_the_universe_in_sound
A very interesting presentation with the history of radio waves discoveries.
5. https://www.youtube.com/watch?v=olVJzVadiFs
Some interesting experiments with the Bernoulli law and Coanda effect
6. http://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=11742
The video reveals the changes on the Sun’s surface. The video is made by many photos.
7. http://earthsky.org/space/ten-things-you-may-not-know-about-the-solar-system
This is a site with 10 curiosities of the Solar System, that can be studied by the students.
8. http://www.jpl.nasa.gov/news/news.php?release=2014-039
These are 2 photos of the Earth made by NASA Mars Rover Curiosity from Mars.
9. http://htwins.net/scale2/
The scale of Universe – a very interesting presentation of all dimensions
10. https://www.youtube.com/watch?v=JvdL3R7fDL4#t=92
A theoretical travel through Universe with the speed of light
11. https://www.youtube.com/watch?v=7NYRVsKAkFM
A comparison of the Earth’s volume with planets and other celestial bodies
12. http://apod.nasa.gov/apod/ap130424.html
An excellent experiment made on ISS for emphasize the superficial tension
13. https://www.youtube.com/watch?v=rhuMfo321RQ
How to put in evidence that the water molecule is an electric dipole?
In the same video you can observe that a sphere of water is a convergent lens.
14. http://shadowsnook.com/MAG/Stuff/NightSky/Pages/004.html
A very good programme to find some constellations on the sky