The radius of the earth's orbit is 92,960,000 miles (on average). sooooo, assuming a circular orbit, how fast (in km/s) does the earth orbit the sun? i get confused becuase i dont know where to begin the dimensional analysis......
2006-08-22 12:57:41 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Given the radius,
r = 92,950,000 miles or
r = 148,720,000 km (using 1 mile = 1.6 km)
Circumference of the circle is:
C = 2 x pi x r
= (2) x (3.142) x (148,720,000) km
= 934,556,480 km
Since the journey takes 1 year, the time taken in second is,
t = 365.25 x 24 x 60 x 60 seconds
= 31,557,600 s
Therefore the speed in km/s is,
= (934,556,480 km) / (31,557,600 s)
= 29.6143 km/s
(or about 18.5 miles/s)
2006-08-22 13:38:51 · answer #1 · answered by ideaquest 7 · 0⤊ 0⤋
First convert the radius to km. pi * 2r will give you the circumference of the circle. You know the time that it takes is one year. Convert this to seconds (3600 s/hr). Divide the circumference by the time in seconds and there is your speed.
2006-08-22 20:24:56 · answer #2 · answered by FlashGordon 3 · 0⤊ 0⤋
First convert 92,960,000 miles to kilometers (km)
then figure the circumference of the circle
Now you know total km. The period of time is one year (365.25 days) convert one year to seconds.
Then divide circumference by the time for km/sec.
I will leave the number to you and your calculator.
2006-08-22 20:01:52 · answer #3 · answered by rscanner 6 · 1⤊ 0⤋
Why is everyone converting to kilometers? MPH works too. circumference = 2pi*r. r=92,960,000 = 584084906 miles.
584084906 miles / 365 days / 24 hr = 66676.36 MPH
2006-08-22 21:45:51 · answer #4 · answered by STEVEN F 7 · 0⤊ 0⤋
18.5 miles per second.
http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Speeds.shtml
2006-08-22 19:59:52 · answer #5 · answered by Anonymous · 0⤊ 0⤋
i used to remember how to do it but i forgot..if you have it somewhere it might be in your book how to calculate it
2006-08-22 20:01:45 · answer #6 · answered by Anonymous · 0⤊ 1⤋