







Distance between a chord and its arc on a circle 
20180323 

From Doug: Specifically, what is the subject distance for the Earth orbiting for 27 days. Assume the orbit of the Earth to be a circle have a 93 million mile radius. Assume the angle of arc to be (27/365) x 360 degrees. Thank you. Answered by Penny Nom. 





Eccentricity of an Elliptical Orbit 
20080820 

From Gina: A satellite has an elliptical orbit around the earth with one focus at the earth’s
center, E. The earth’s radius is 4,000 miles. The highest point that the satellite is
from the surface of the earth is 800 miles, and the lowest is 200 miles.
What is the eccentricity of the satellite’s orbit? Answered by Janice Cotcher. 





Orbital velocity 
20060215 

From Lizzie:
Assume the world is a spherical planet with a diameter of 1600 KM. with a uniform density or 5200 KM.
It the moon is in a circular orbit of 630 KM. above the surface of the world,what is it's orbital velocity in metres per second?Round to the nearest WHOLE number.
Answered by Stephen La Rocque. 

