In 1895, a physicist named Wilhelm Roentgen
was doing experiments with a cathode tube,
a glass container in which a beam of electrons lights up a fluorescent window.
He had wrapped cardboard around t
分类目录归档:rays
In 1895, a physicist named Wilhelm Roentgen
was doing experiments with a cathode tube,
a glass container in which a beam of electrons lights up a fluorescent window.
He had wrapped cardboard around t