<http://webisa.webdatacommons.org/6179374>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/6179374>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<citizendium.org> .
<http://webisa.webdatacommons.org/6179374>	<http://www.w3.org/ns/prov#value>	"In physics, an electromagnetic wave is a change, periodic in space and time, of an electric field E(r,t) and a magnetic field B(r,t)." .
<http://webisa.webdatacommons.org/prov/79076752>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/6179374> .
<http://webisa.webdatacommons.org/prov/34394317>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/6179374> .