Chapter 2, Problem 5P

### College Physics

11th Edition
Raymond A. Serway + 1 other
ISBN: 9781305952300

Chapter
Section

### College Physics

11th Edition
Raymond A. Serway + 1 other
ISBN: 9781305952300
Textbook Problem

# Two boats start together and race across a 60-km-wide lake and back. Boat A goes across at 60 km/h and returns at 60 km/h. Boat B goes across at 30 km/h, and its crew, realizing how far behind it is getting, returns at 90 km/h. Turnaround times are negligible, and the boat that completes the round trip first wins. (a) Which boat wins and by how much? (Or is it a tie?) (b) What is the average velocity of the winning boat?

(a)

To determine
The boat which wins and the distance between them.

Explanation

Given Info:

The speed of boat A is 60â€‰km/h .

The length of the lake is 60â€‰km .

The speed of boat B when moves across the lake is 30â€‰km/h .

The speed of boat B when it returns is 90â€‰km/h .

Explanation:

The formula used to calculate the time taken by boat A to cross the lake is,

Î”tA=Î”xAvA

• Î”tA is the time taken to go across the lake by boat A
• Î”xA is distance covered by the boat A
• Î”vA is the velocity of boat A

Substitute 60â€‰km for Î”xA , 60â€‰km/h for vA to find Î”tA .

Î”tA=60â€‰km60â€‰km/h=1â€‰h

The boat A moves across the lake in one hour and returns in next hour

(b)

To determine
The average velocity of the winning boat.

### Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

#### The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started