Which statement is a part of Dalton’s atomic theory? A. Atoms are composed of protons, neutrons, and electrons.
B. Elements can have atoms that are isotopes.
C. One type of atom cannot be changed to another type by a chemical reaction.
D. Electrons move around the nucleus in an electron cloud.

Abookcase has a mass of 38 kg and the coefficient of friction between it and the floor is 0.82 what is the maximum force of friction between the bookcase and the floor a 372n b 305n c 412n d 449n

Two steel balls, each of mass m, are welded to a light rod of length l and negligible mass and are initially at rest on a smooth horizontal surface. a horizontal force of magnitude f is suddenly applied to the rod as shown. determine (a) the instantaneous acceleration a of the mass center g and (b) the corresponding rate at which the angular velocity of the assembly about g is changing with time.

The discovery of the electron as a subatomic particle was a result of