Hans Christian Oersted, in year 1820 he initiated the discovery of relationship between electricity and magnetism. He accidentally brought the compass close to the wire and the needle of the compass twitched after that happen he said that there have a magnetic effect happen on electric current.
So today we have a graded recitation. You need to explain each scientist how they invented.
The second one is Andre-Marie Ampere, some time in year 1820 he heard about Oersted discovery and decided to make own experiment too. He usedtwo wires side by side and he made the two electric currents flow in the same direction, by this two wires it has ATTRACTION, If the direction is opposite it may have REPULSION. see? there's a Attraction and Repulsion of wire by running current trough the wires and changing its direction without the use of any magnets. He proves that All of it was Generated By Electricity. He called it ELECTRODYNAMICS.
The 3rd scientist, in year 1832 Micheal Faraday reversed the discovery of Oersted and Ampere. By his experiment he used solenoid and galvanometer to detect the presence of current when he started to try it the needle of galvanometer move, it means the current was detected. He observed that the current is detected when the magnet is moving so the magnetic field can produces a electric current. He called it ELECTROMAGNETIC INDUCTION.
James Clerck Maxwell. In year 1864 The discovery Oersted and Faraday was his basis to study if the ELECTRICITY and MAGNETISM combine into one unified theory. Then hetranslate findings of Faraday into mathematical equation and he develop ELECTROMAGNETIC THEORY and he added on Faraday discovered the CONVERSE. Electric charge or Electric current don't need a charge to propagate Electromagnetic wave based on his theory. But he cant prove the EM waves trough experiments.
Heinrich Hertz his set up about his experiment simple spark generator, couple 2 of antenna and metallic ring, when he turned on the generator the spark was seen in a metallic ring gap.He discovered the radio waves a form of EM waves.