# In 2015, the U.S. national debt was about $18 trillion. (a) If payments were made at the rate of$1 000 per second, how many years would it take to pay off the debt, assuming that no interest were charged? (b) A dollar bill is about 15.5 cm long. If 18 trillion dollar bills were laid end to end around the Earth’s equator, how many times would they encircle the planet? Take the radius of the Earth at the equator to be 6 378 km. ( Note: Before doing any of these calculations, try to guess at the answers. You may be very surprised.)

### College Physics

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

### College Physics

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

#### Solutions

Chapter
Section
Chapter 1, Problem 78AP
Textbook Problem

## Expert Solution

### Want to see the full answer?

Check out a sample textbook solution.See solution

### Want to see this answer and more?

Experts are waiting 24/7 to provide step-by-step solutions in as fast as 30 minutes!*

See Solution

*Response times vary by subject and question complexity. Median response time is 34 minutes and may be longer for new subjects.