Nonconjugated β,γ-unsaturated ketones are in base-catalyzed equilibrium with their conjugated α,β-unsaturated isomers. The mechanism of interconversion involves the formation of a resonance-stabilized intermediate with three resonance contributors. Draw the structures of these three resonance contributors.

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.

Which of the following situations is impossible? a) an object has velocity directed east and acceleration directed east. b) an object has zero velocity but non-zero acceleration. c) an object has constant non-zero velocity and changing acceleration. d) an object has velocity directed east and acceleration directed west. e) an object has constant non-zero acceleration and changing velocity.

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.