SOLUTION: A line from the sun to the Earth sweeps out an angle of how many radians in 73 days? Can someone help be with this? Thank you.

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Question 1077720: A line from the sun to the Earth sweeps out an angle of how many radians in 73 days?
Can someone help be with this?
Thank you.

Found 3 solutions by math_helper, ikleyn, KMST:
Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!
In approx 365 days, the Earth sweeps 360 degrees.
360 degrees = +2pi+ radians
(73days/365days)*2%28pi%29+ = 0.4%2Api+=+highlight%282pi%2F5%29+ radians

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The above of course assumes the Earth's orbit is a circle with distance from the sun of 93million miles.
To answer the question from your thank you message, if we assume a circular orbit, and 93million miles from the sun, and an exact 365 day year, then the linear speed of the earth is 2%28pi%29+%2A+93x10%5E6+%2A+%281%2F365%29+%2A+%281%2F24%29+=+66705+ mi/hr

Answer by ikleyn(52817) About Me  (Show Source):
You can put this solution on YOUR website!
.
Let use the simplest conception:

     "the Earth moves uniformly on a circular orbit around the sun and makes 1 full revolution in 365 days"

Then your angle is %282%2Api%29%2A%2873%2F365%29 radians.


6.28%2A%2873%2F365%29 = 1.256 radians.



Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Not knowing when those 73 days occur,
we can give only an approximate average,
but it does not matter because we are not astrophysicists,
expected to know the exact period of Earth
(about 365.25 days, but variable), and
according to Kepler's laws of planetary motion, in equal times
that line sweeps equal area sectors of Earth's elliptical orbit (not equal angles).
For math class purposes (but don't say that to your space science teacher),
Earth does one turn, 2piradians , around the sun in 365days ,
at a constant angular velocity of.
2pi%2F365 radians per day.
In 73+days, the angle swept would be
2pi%2A73%2F365radians=0.4piradians=about1.257radians .