Parallax in Observing Stars. Created by Sal Khan.
Parsec Definition. Created by Sal Khan.
In this activity, students observe fluid motion and the formation of convection cells as a solution of soap and water is heated. This procedure can be performed as a demonstration by the teacher, or older students can conduct the experiment themselves. A list of materials, instructions, and a description of the convective process are included.
Plates Moving Due to Convection in Mantle. Created by Sal Khan.
Plate Tectonics Introduction and Difference between crust and lithosphere. Created by Sal Khan.
Plate Tectonics -- Evidence of plate movement. Created by Sal Khan.
Geological features of Convergent Plate Boundaries. Created by Sal Khan.
Plate Tectonics -- Geological Features of Divergent Plate Boundaries. Created by Sal Khan.
How K-Ar dating can be used to date very old volcanic rock and the things that might be buried in between. Created by Sal Khan.
Clarifying the effect of axial precession on the calendar and the date of perihelion and aphelion. Created by Sal Khan.
Quasar Correction. Created by Sal Khan.
Quasars. Created by Sal Khan.
Radius of Observable Universe. Created by Sal Khan.
(Correction) Radius of Observable Universe. Created by Sal Khan.
Sal's random predictions for the year 2060. Created by Sal Khan.
An introduction to red shift
Refraction of Seismic Waves. Created by Sal Khan.
Students explore orbit transfers and, specifically, Hohmann transfers. They investigate the orbits of Earth and Mars by using cardboard and string. Students learn about the planets' orbits around the sun, and about a transfer orbit from one planet to the other. After the activity, students will know exactly what is meant by a delta-v maneuver!
The nearest stars to our solar system, are located in the Alpha Centauri system. The two main stars are Alpha Centauri A and Alpha Centauri B, which are approximately 4.3 light years away from Earth. The third star in the Alpha Centauri system, Proxima Centauri, is actually the closest star to our solar system at approximately 4.2 lightyears away from Earth. Created by Sal Khan.
Scale of Earth and Sun. Created by Sal Khan.