EJERCICIO ADICIONAL:
Para completar algunos aspectos relativos a la conexión Sol-Tierra y sus efectos sobre el campo magnético terrestre es interesante resolver las cuestiones que se plantean en el ejercicio disponible en este link
También puede consultarse este enlace sobre construcción de magnetómetros
...PARA CURIOSOS
La ONG EARS TO OUR WORLD se dedica a promover la radio en HF como la tecnología más adecuada para potenciar la educación en zonas remotas,rurales y empobrecidas.
En su página WEB explican muy bien las ventajas de la radio:
WHY ARE RADIOS IMPORTANT IN AN INTERNET WORLD?
In many countries, access to the “information economy,” the networking technology which instantaneously connects people across the planet with information, media, and each other, is now often seen as a basic human right.
Unfortunately, much of the world does not have the communications infrastructure to support access to the world wide web and other dynamic media sources such as digital television, wireless networks or even the telephone. Political instability, meanwhile, can undermine even the written word.
For many people living in poverty or in war-torn regions, radio is still the best and most effective way to receive life-supporting information. However, even radios, a technology many of us now take for granted, are out of reach for those who live on less than $1.00 US per day.
That’s where we come in. The simple gift of a wind-up radio, especially one which does not require expensive batteries, which provides a light for those who want to read or work or care for the sick, and which is simultaneously a source of enlightenment, entertainment, and empowerment, can truly be the world to those we serve.
