Calculating Angular Velocity: Earth's Rotation & Orbital Speed

Click For Summary
The Earth rotates on its axis once every 24 hours and orbits the sun once every 365.24 days. The average angular velocity for Earth's rotation is calculated using the formula Wavg = Delta Theta / Delta Time, where Delta Theta is 2 Pi radians. This results in an angular velocity of approximately 7.27 * 10^-5 radians/second. However, the calculations for both the Earth's rotation and its orbital speed around the sun, which was found to be 1.99 * 10^-7 rad/sec, were flagged as incorrect by the WebAssign homework program. Clarification is sought on the errors in these calculations.
IAmSparticus
Messages
36
Reaction score
0
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?
 
Physics news on Phys.org
What are the questions?

AM
 
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?

Similar threads

  • · Replies 1 ·
Replies
1
Views
7K
Replies
13
Views
1K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
9K
  • · Replies 4 ·
Replies
4
Views
11K