According to classical physics what should happen as a filament in a light bulb gets hotter?

“other instruments such as gravimeters and magnetometers are also used in the search for petroleum. extracting crude oil normally starts with drilling wells into an underground reservoir. when an oil well has been tapped, a geologist (known on the rig as the "mudlogger") will note its presence. “ this is what i found on google i hope it

Need more information like a picture

If element x has 21 protons, element x has 21 electrons