5.2 Specify if the materials named in the previous exercise are conductors or insulators, underlining only the conductors. To underline a multi-word expression (if necessary), click each word individually.
Aluminium • copper • glass • plastic • rubber • sea water • silver • wood • iron • steel
6. Listen to the history of superconductors and complete the sentences using no more than four words.
1. Superconductivity was discovered in . 2. The scientist who studied conductivity was a called H. K. Onnes. 3. He discovered that the disappeared when it was cooled down to −269 °C. 4. His experiment consisted in applying an to cooled mercury, then disconnecting the battery. 5. He found out that electric current persisted in the mercury and . 6. This confirmed the . 7. In 1986, Bednorz and Muller discovered which could be superconductors. 8. in the field of superconductors has not stopped yet. 9. Hydrogen have been studied since 2015. 10. They reach superconductivity at but at .