Is physics singular or plural? For example, in the sentence "The uncertain physics of convective and circulatory flows need/needs to be addressed" should the verb properly be "need" or "needs"?
Physics, while plural in derivation, is generally construed as a singular noun except when referring to several "physics" (i.e., two or more different systems of physics). In this sentence, where the meaning is "uncertainty in the field of physics," the singular form "needs" would be correct.