Chapter 2, Problem 2.21CP

(a)

Interpretation Introduction

Interpretation:

Whether the work done is positive, negative or zero if a bowling ball rolls across a table.

Concept Introduction:The work of a system at some height depends on the potential energy, if potential energy is increased, work is positive and if it is decreased it is negative. For the process in which no change in the potential energy takes place, the work done is zero.

(b)

Interpretation Introduction

Interpretation:

Whether the work done is positive, negative or zero if a bowling ball falls on the floor.

Concept Introduction:The work of a system at some height depends on the potential energy, if potential energy is increased, work is positive and if it is decreased it is negative. For the process in which no change in the potential energy takes place, the work done is zero.