Articles: Sunglasses that Switch On and Off (200), Levitation of a Manget over a Superconductor (205), Juggling and the Theorist (221). Notes: Unexpecte Result (204), What Is Physics? (225), How to Test Your PK Power (228), Heating the Hard Way (240), Physics Haiku (244). Departments: Editorial (1989), Letters (199), In My Opinion (246), Figuring Physics (248), Book Reviews (249), How Things Work (252), AV Corner (254), Etcetera (255).

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