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Tricks67
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the conservation of angular momentum applied to Earth as well right? but doesn't Earth's rotation go through seasonal variations, is the angular momentum still conserved?
Those external torques are however very small. The largest of these external torques causes the orientation of the Earth's rotation axis to precess over a 26,000 year period. This lunisolar precession changes the axis of rotation, but not the rate of rotation. Tidal friction does change the Earth's rotation rate, but this is extremely slow. Length of day was about 21.9 hours 620 million years ago. Over the course of a year, or even a century, this change in length of day is very small.JHamm said:The conservation of angular momentum applies to any system with no net torques.
After accounting for all known external torques, there is a very observable seasonal variation in length of day. So what explains this?Tricks67 said:the conservation of angular momentum applied to Earth as well right? but doesn't Earth's rotation go through seasonal variations, is the angular momentum still conserved?
Tricks67 said:the conservation of angular momentum applied to Earth as well right? but doesn't Earth's rotation go through seasonal variations, is the angular momentum still conserved?
It's best to qualify that "solar day" with the word "apparent." There's also a "mean solar day," which is nearly constant.256bits said:The change in solar day from season to season can be explained by the orbit of the Earth not being an exact circle, but rather an ellipse; and the tilt of the Earth's axis of rotation.
Earth's rotation refers to the spinning of the Earth on its axis, which causes day and night. This rotation also creates the Coriolis effect, which affects the direction of winds and ocean currents. It also plays a role in the formation of seasons and the length of our days and nights.
Angular momentum conservation is a fundamental principle in physics that states that the total angular momentum of a system will remain constant unless acted upon by an external torque. In the case of Earth's rotation, the distribution of mass and the Earth's shape help to maintain its angular momentum.
The Earth's rotation causes it to bulge at the equator and flatten at the poles, resulting in an oblate spheroid shape. This is due to the centrifugal force created by the rotation, which is strongest at the equator and causes the Earth to bulge outward.
Yes, the Earth's rotation can change over time due to various factors such as tides, changes in Earth's mass distribution, and celestial events. However, these changes are typically very small and may not be noticeable in our daily lives.
Earth's rotation is measured using techniques such as satellite laser ranging and Very Long Baseline Interferometry (VLBI). These methods track the movements of specific points on Earth's surface and compare them to a reference point to determine the rate and changes in Earth's rotation. This data is then used to adjust Coordinated Universal Time (UTC) to account for the Earth's rotation slowing down or speeding up.