Question

as an unread romance novel falls off the top of a building it speeds up until it hits the ground. as the book is falling its kinetic energy _, its potential energy _, and its total energy ___. neglect the effects of air resistance. a increases; decreases; increases b increases; decreases; decreases c decreases; increases; is constant d increases; decreases; is constant

Explanation:

Step1: Recall energy - conservation principle without air - resistance

When the book falls from the top of the building, its height \(h\) decreases. The gravitational potential energy is given by \(U = mgh\) (where \(m\) is mass, \(g\) is the acceleration due to gravity and \(h\) is height), so the potential energy decreases.

Step2: Analyze kinetic energy

As the book falls, its speed \(v\) increases. The kinetic energy is given by \(K=\frac{1}{2}mv^{2}\), so the kinetic energy increases.

Step3: Analyze total energy

Since there is no air - resistance, the total mechanical energy \(E = K + U\) is conserved.

Answer:

A. increases; decreases; is constant