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sanidhay
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what does this mean that every year the time of daylight in increasing on a specific date? is the speed of Earth's rotation increasing or the speed of its revolution is increasing..please help me out...
sanidhay said:what does this mean that every year the time of daylight in increasing on a specific date? is the speed of Earth's rotation increasing or the speed of its revolution is increasing..please help me out...
mathman said:The main reason for seasonal variation of the time of daylight is the direction of the Earth's axis relative to the sun. On Dec. 21 the north pole is tilted as far as possible away from the sun and on June 21 the north pole is pointed as close as possible toward the sun. Net result from Dec 21 to June 21 daylight increases in the northern hemisphere and decreases in the rest of the year. In the southern hemisphere the daylight variation is reversed.
nasu said:Are you talking about the "daylight saving" programs?
It doesn't - so what do you mean?sanidhay said:But can it be possible that the daylight will be of 23 hours and 9 minutes?
if yes then what does it means?
suppose on a given day after every year the time of daylight increase by 1 minute...then what does this mean?
sanidhay said:no i m not talking about them
sophiecentaur said:Look at this animation and also google "day length and Earth tilt".
Day length is a matter of what proportion of daily rotation gets sunlight on a particular place on the globe. If you're on the Pole, during the summer, there is sunlight all day and in winter it's dark all day. Nearer the equator, the light / dark is a pretty even split at all times.
The Earth tilts the same way (in absolute terms) wherever it is around its yearly orbit - see the animation then figure it out.
nasu said:Then it is not true that the "the time of daylight in increasing on a specific date".
The time of daylight increases and decreases continuously and periodically during the year.
There is no specific date when is increasing. There are specific dates corresponding to the minima and maxima of the cycle (the solstices).
Still not clear what are you talking about.
now got it?russ_watters said:It doesn't - so what do you mean?
sophiecentaur said:Did you not notice that it is DECREASING in the Autumn?
Did you READ this or CALCULATE it? What info did you use?sanidhay said:whatever it does but on December 21 56994 the sunlight will be of 23 hours and 6 mins...
what say about this?
i calculated this...sophiecentaur said:Did you READ this or CALCULATE it? What info did you use?
sanidhay said:whatever it does but on December 21 56994 the sunlight will be of 23 hours and 6 mins...
what say about this?
i used 21 december because it has the shortest period of daylight...and wolframalpha is a software from creators of google...nasu said:And what will be the length of the night on the same day?
The explanation for your observation will depend on what that software is doing. I mean, first has to be established if this is a real fact or just something wrong in the software.
Predicting the length of the day for long periods and taking into account all the perturbative factors is not an easy task. It may be just first order approximation, which works well for 100 years but breaks down for many thousands.
Second, picking up a specific day (September 21) is not the best choice. The length of the day depends on how far from the solstice you are. The solstice does not "happen" always on September 21.
nasu said:You mean Wolfram alpha has a built in function to calculate the length of the day?
When I ask about the software I mean a specific application, based on some model. Not the computer program or computation environment used to run the application.
Not necessarily. The solstice may occur in the period 20-22 December.sanidhay said:i used 21 december because it has the shortest period of daylight...
and tht includes 21 toonasu said:Not necessarily. The solstice may occur in the period 20-22 December.
the data is taken from wolframalpha only...go and check it outsophiecentaur said:You are not answering our question. Where does your DATA come from? (Not Wolfram, I suggest)
sanidhay said:the data is taken from wolframalpha only...go and check it out
December 21 56994
sanidhay said:whatever it does but on December 21 56994 the sunlight will be of 23 hours and 6 mins...
what say about this?
sanidhay said:i don't know ne thing about that...
but just assume that it is happening...
i just want to know that if it is happening thn what is the factor responsible for that?
this was the answer i was wantingruss_watters said:Perhaps you are talking about the slowing of Earth's rotation? This happens due to tidal friction, but it is a very small effect. Your posts implied something bigger.
sanidhay said:this was the answer i was wanting
just fyi though, that amount is 1.7 microseconds per century, which is a lot smaller than what you saw.sanidhay said:this was the answer i was wanting
How do you know that is built into the Wolfram software? Is it made at all clear in the documentation? If not, it is no proof one way or another. You need a scientific approach if you want a reliable answer.sanidhay said:this was the answer i was wanting
Changes in Earth's rotation and revolution speeds occur due to various factors, such as the gravitational pull of the moon and other planets, changes in the distribution of mass on Earth's surface, and natural phenomena like earthquakes and volcanic eruptions.
Changes in Earth's rotation and revolution speeds can affect our daily lives in small ways, such as the length of our days and seasons, and can also have larger impacts on weather patterns and ocean currents.
Scientists use a variety of methods to measure changes in Earth's rotation and revolution speeds, including satellite data, astronomical observations, and precise measurements of the Earth's position and movement.
While changes in Earth's rotation and revolution speeds are a natural occurrence, they can have some consequences, such as changes in climate patterns and potential disruptions to navigation systems. However, these changes are typically very gradual and do not pose an immediate threat to human life.
Humans have a minimal impact on changes in Earth's rotation and revolution speeds. However, activities such as the melting of polar ice caps and the extraction of natural resources can contribute to changes in the distribution of mass on Earth's surface, which can affect the planet's rotation and revolution speeds over long periods of time.