Physics textbook errata - Serway & Faughn

From Mike Benjamin

Anonymous Submissions

Problem 9, chapter 13 (the pogo stick):

Their solution assumes that the spring in the pogo stick extends past equilibrium as you rise up off the ground: that amounts to gluing the bottom of the pogo stick to the ground & bouncing up and down on it with the tip never leaving the ground. The spring should just return to equilibrium and stay there as it leaves the ground.

Chapter 14, problem 23 page 460

The problem reads: At rest, a car's horn sounds the note A (440 Hz). The horn is sounded while the car is moving down the street. A bicyclist moving in the same direction with one-third the car's speed hears a frequency of 440 Hz. How fast is the car moving? Book's answer: 32.1 m/s

If they both hear 440 Hz, the car and bike must be traveling at the same speed in the same direction. Since the bike has a speed of 1/3 the car's speed, they must both be at rest.

If you look in the student solution manual, you'll see that they assume the bicyclist hears 415 Hz, which gives the answer in the back of the book. The 440 for the bicyclists speed is a typo, and should actually be 415 Hz.