Earth's Rotation Day 2025 is on Wednesday, January 8, 2025: Physics problem: duration of days relative to Earth's decreasing rate of rotation.?
Wednesday, January 8, 2025 is Earth's Rotation Day 2025. SkyTellers - Day and Night Activity - The Cycle of Light Earth's rotation causes
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Ever feel like you're simply spinning around and around? Do not worry-- most of us are, constantly! Planet's Rotation Day is a little reminder that we're all turning uncontrollable, and there's absolutely nothing that we could do regarding it.
Decreasing rate of rotation means the angular velocity of the earth is decreasing.
Earth's rate of rotation is continuously decreasing, which causes days to last increasingly longer. In the year 2000, it took Earth 0.548 seconds longer to complete 365 revolutions than it did in 1900.
100 years * 365 days/yr * 24 hr/day * 60 min/hr * 60 s/min = 3.1536 * 10^9 seconds
Initial time for 365 revolution = 365 day * 24 hr/day * 60 min/hr * 60 s/min
Time for 365 revolution = 3.1536 * 10^7 seconds
100 years later, time for 365 revolution = 3.1536000548 * 10^7seconds
One revolution = 2 * π radians
365 revolutions = 730 * π radians
Initial angular velocity = 730 * π ÷ 3.1536 * 10^7
Final time for 1 revolution = 86,400.00150137
Final angular velocity = 730 * π ÷ 3.1536000548 * 10^7
Average angular acceleration = [(730 * π ÷ 3.1536000548 * 10^7) – (730 * π ÷ 3.1536 * 10^7)] ÷ 3.1536 * 10^9
Average angular acceleration = -3.9485 * 10^-22 rad/s^2
b) If said average acceleration is constant, in what year with Earth's rotation cease?
α = (ωf – ωi) ÷ t
α = -ωi ÷ t
Time = -ωi ÷ a
Final angular velocity = 0
Initial angular velocity = 730 * π ÷ 3.1536 * 10^7
Time in seconds = (-730 * π ÷ 3.1536 * 10^7) ÷ -3.9485 * 10^-22 = 1.84 1764 * 10^17
1 year * 365 days/yr * 24 hr/day * 60 min/hr * 60 s/min = 3.1536 * 10^7 seconds
Time in years = [(-730 * π ÷ 3.1536 * 10^7) ÷ -3.9485 * 10^-22] ÷ 3.1536 * 10^7
Time in years = 5.84 * 10^9 years
If the moon determines months and the earth's rotation determines days....?
Each week is one quarter phase of the moon. A full moon to a new moon takes two weeks, then another two to return. For practical purposes it was easier for early civilisations to split things into 7 rather than deal with a 14 day week. Interestingly civilisations across the globe developed a 7 day week independantly to each other. Days months and weeks were pretty uniform measures of time with only years changing because they were not measured accurately or influenced by religion. As cultures came into contact with each other it was helpful to have similar measurements of time for purposes of trade also. The two largest civilsations to develop seven days was China (and Japan) and the West: From as early as Babylon through ancient Egypt and Rome.
What is Earth's rotation?
One cycle of the Earth's rotation on its axis is called a day. This is 1440 minutes long, if the average solar crossing of your local meridian is used as the reference, or about 1436 minutes long if the reference is to the passage of stars past your local meridian.
