mechanical stress vs physics

mechanical stress and physics both are nouns.

Word	Noun	Adjective	Verb	Adverb
mechanical stress	Yes	No	No	No
physics	Yes	No	No	No

mechanical stress (noun)	physics (noun)
elastic stress (any deformation of a solid material) and viscous stress (the gradual changing of the deformation) combined.	the science of matter and energy and their interactions
	the physical properties, phenomena, and laws of something