# National debt

1. 1. Determine the distance between Earth and the Moon’s surface in kilometers. 2. Convert your answer from #1 above to miles. 3. How many Earths away from the sun Pluto is. To do this, put Pluto in the center of your screen and change the unit of measurement above the ruler along the bottom of the page to “Earths” 2.Open a new tab and go to the website Space Place (opens in new tab) and find the average distance from the Earth to our moon. Use the average distance and calculate the percentage error of your estimate from part 2 above. If your error is greater than 50%, then go back to question 1 and START OVER! [URL: https://spaceplace.nasa.gov/moon-distance/en/] Enter your final percent error here. (Note: this answer should be between -50% and 50%). 3. The escape velocity from planet Earth is 11,184.7258 meters per second. If a rocket ship reaches this speed and maintains it, then neglecting the need to slow down prior to landing, how many HOURS would it take the rocket ship to reach the moon? (Use the average distance from #3 when answering this question.) Round to two decimals. 4. Look up the MINIMUM distance from Earth to Pluto. A rocket ship traveling at 36,695.2946 feet per second will take how many YEARS to reach Pluto? Round to two decimals. 5. Look up the MAXIMUM distance from Earth to Pluto. A rocket ship traveling at 36,695.2946 feet per second will take how many YEARS to reach Pluto? Round to two decimals. 6. Use the debt clock website (opens in new tab) to find the amount of the U.S. national Debt as accurately as possible. What is the national debt you found? [url: https://www.usdebtclock.org/] 7. If you stacked dollar bills, then how many miles tall would the national debt be? (Note: A dollar bill is 0.0043 inches tall.) Round to two decimals. 8. The circumference of Earth’s moon is 6,783.5 miles. Using your previous answer, how many times around the moon would the national debt go? 9. Pluto has been hard to measure from Earth because of its atmosphere. In 2007 Young, Young, and Buie measured Pluto as having a diameter of 2322 km. In 2017 new measurements were taken and Pluto is now believed to be 2376.6 km in diameter. Since the older measurement is now considered incorrect, what was the percent error of the 2007 measurement? [enter your answer as a percentage without the % sign] Round to two decimals. 10. The dwarf planet Eris has no atmosphere and has been easier to measure than Pluto. At its largest, the diameter of Eris is 2,338 km. Pluto’s largest diameter measures 2,379.8 km. As a percent difference, how much larger is Pluto than Eris at their largest diameters? As a percent difference, how much smaller is Eris than Pluto at their largest diameters?