This is something everybody with some experience from cooking knows. If a potato has lost water and become dehydrated, wrinkled and soft it will regain its form by putting it into fresh water for some hours. If you put a fresh potato into salt water it will behave opposite. It shrinks and becomes sloppy and soft. It is the water in the cellular juice that moves one way or the other through the cellular membrane and thus will enlarge/shrink the juice pressure in the cells.

This is a small test containing various tasks and questions. The last page in this test will display your result. Not all the names of the tasks are displayed in the result section, for some tasks only the points are displayed.

This kind of test can easily be made and used in the LMS area of all learning portals. At the end of the test, it's recomended that you write your e-mail address so that the result can be sent to you.

A heat pump does two energy(heat)- exchanges (one on the outside and one on the inside), and a loop that carries the energy from one place to another by using a work medium. The work meidum is normally R410A, called Puron. Follow the arrow in the large loop and see how the medium changes its state from liquid to gas and back to liquid by doing pressure changes and energy exchanges.

This is a task where the student is pairing pictures, text, expression after a condition that characterise the pair. It may be a mathematical expression, gramathics, animal classification, chemical reactions, physical laws and so on.

The two nuclear reactions that give great amounts of energy are fission (splitting of heavy atom nucleuses) and fusion (melting light atom nucleuses together). It is only the fission process that we can control and use for energy exploiting.

The animation possibilities in MultiMedia Lab can be used to make qualitative models describing the behaviour simple and illustrative.