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physical science vs. physics

noun

physical sciences plural
  1. any of the natural sciences dealing with inanimate matter or with energy, as physics, chemistry, and astronomy.

  2. these sciences collectively.

[fiz-iks] / ˈfɪz ɪks /

noun

(used with a singular verb)
physics plural
  1. the science that deals with matter, energy, motion, and force.