Average Angular Velocity of the Earth?

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The average angular velocity of the Earth is calculated based on its rotation and orbit. The Earth completes one rotation every 24 hours, resulting in an angular displacement of 2π radians. However, this calculation must account for the Earth's orbital movement, which slightly alters the effective rotation angle in one day. The correct average angular velocity for the Earth's rotation is approximately 7.27 x 10^-5 radians/second, but adjustments are needed for orbital motion to find the angular velocity around the sun, which is about 1.99 x 10^-7 radians/second. The misunderstanding arises from not factoring in the Earth's orbital progress during its daily rotation.
IAmSparticus
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1. The Earth spins on its axis once a day and orbits the sun once a year (365.24 days). Take the positive direction for the angular displacement to be the direction of the Earth's motion. Express your answers in radians/second.



2. Wavg = Delta Theta / Delta Time
Delta Theta is in radians



3. Since the Earth rotates once during a day, the delta theta equals 2 Pi radians.
Time = 60 seconds (in a minute) * 60 minutes (in an hour) * 24 hours (in a day) = 84600 seconds.
2 Pi radians / 84600 seconds = 7.27 * 10^-5 rads/sec

Appartenly this is wrong accoring to the homework program WebAssign. What is wrong with my work?

Also, I got 1.99 * 10^-7 rad/sec for the angular velocity of the Earth around the sun, which is apparently also wrong.

Help?
 
Last edited:
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Rotation in 1 day is not exactly 2π, since in that time the Earth has moved along 1/365.24 of it's orbit.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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