A student adding iron filings to sulphur using a strong magnet to demonstrate that those same iron filings can be extracted from the sulphur with the same magnet. | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Hutchings, Richard |
Taille de l’image : | 3614 px × 2689 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |