Is a Day Really 24 Hours? Exploring the Concept of Time and How We Measure It

  • Thread starter darksoda
  • Start date
In summary, the day begins at 00:00 a clock for example if the day 1 begin at 00:00 a clock ends 23:59 and 59 secounds right ?? so isn't 24 hours cause lack 1 secound right? thanks for future answers.
  • #1
darksoda
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Hey peple i always have this doubt ^^ the people say the day have 24 hours right? so the day begin at 00:00 a clock for example if the day 1 begin at 00:00 a clock ends 23:59 and 59 secounds right ?? so isn't 24 hours cause lack 1 secound right? thanks for future answers.
 
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  • #2
Hi, darksoda,
the last second of the day begins at 23:59:59, but the day does not end at the beginning of the last second; it ends at the end of the last second.

It's like having 10 Lego blocks in a row, and measuring only 9 because you measure from the beginning of the first block to the beginning of the last block.
 
  • #3
thanks for the answer so let's see if i understand ^^ 0:00 is other day right ? so this one secound is counted before 0:00 ?
 
  • #4
Its sort of for the same reason that when you go on a vacation you stay for seven days but only for six nights. You are counting by the end point, but as Dodo said the more important thing to count is the duration of the whole second.
 
  • #5
Well, this is similar to asking how many times in a day does the hour hand point to 12.

If one meant "in a day" to mean a single instance of a day, then the end points of the day are included and the answer is 3 because it starts at 12, passes 12 at noon, and ends at 12.

But, if "in a day" was meant to mean over some series of days, then you have to adjust the idea of a day length so as to not count the 12's twice as the ending of one day and the beginning of the next. Each day length interval has one end point included and the other open... with an additional interval end point either at the beginning or end of the series.

So you set a convention that either says 12 is the beginning of a day, or 12 is the end of a day when two days are contiguous. That gives each day 2 12's but leaves on extra 12 either at the beginning or end of the series of days, depending on which convention you choose.

So for one day you would have 3 12's (1x2)+1... (stealing the formula from below, but this is not how the calculation would be for the one day instance; but its consistent)
For two days, 5 12's (2x2)+1
three days, 7 12's (3x2)+1
So number of days=N, then number of 12's is (Nx2)+1

The series trends to 2/day...
1 day->3/1=3
2 days->5/2=2.5
3 day->7/3=2.3333
100 days-> (201 12's)/100=2.01
1000 days-> (2001)/1000=2.001
10,000 days->20,001/10,000=2.0001

...where the indefinite length of the series of days allows the number of 12's "per/day" to be general ("2"), for any finite segment of the indefinite series where either convention gives each day one inclusive and one exclusive end point for its length interval.
But that must be seen similar to a "rate". The number of actual 12's counted in a finite series of days standing apart from the indefinite series must include the additional 12 that is the beginning or end of the finite series, depending on the convention chosen.
 
  • #6
darksoda said:
thanks for the answer so let's see if i understand ^^ 0:00 is other day right ? so this one secound is counted before 0:00 ?
0:00:00 is the exact frontier between last night and this morning. The numbers are, so to speak, located *between* the span of the whole seconds: the first second begins at 0:00:00 and ends at 0:00:01, the 2nd second goes from 0:00:01 to 0:00:02, and so on.
 
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  • #7
thanks for all who answer so we really count the final secound ^^
 
  • #8
Look at a watch, when the second hand is on 59 it takes 1 second to flick to 00. This is the 60th second.
 
  • #9
darksoda said:
thanks for all who answer so we really count the final secound ^^
Why wouldn't we? Any time before 00:00:00 counts as the same day, because 00:00:00 is exactly when the next day starts. So, between 11:59:59 and 00:00:00 is one second of time passing in the same day.
 

1. Is a day really 24 hours?

Yes, a day is defined as 24 hours in most societies and is based on the Earth's rotation on its axis. However, the exact length of a day can vary slightly due to factors such as the Earth's orbit around the sun and the tilt of its axis.

2. How long is a day on other planets?

The length of a day on other planets varies greatly. For example, a day on Mercury is about 176 Earth days, while a day on Venus is about 243 Earth days. On the other hand, a day on Mars is only slightly longer than a day on Earth, at 24.6 hours.

3. How do scientists measure a day?

Scientists measure a day based on the Earth's rotation on its axis, which is defined as one complete rotation. This can be measured using a device called an Earth rotation monitor, which uses precise measurements of the stars to track the Earth's rotation.

4. Why is a day divided into 24 hours?

The division of a day into 24 hours is based on the ancient Sumerian counting system and has been used by many societies throughout history. It is also based on the concept of dividing a day into equal parts, as the number 24 has many factors.

5. Can a day ever be longer or shorter than 24 hours?

Yes, a day can vary in length due to factors such as the Earth's rotation slowing down or speeding up. This can be caused by natural events such as earthquakes or volcanic eruptions, or by human activities such as the use of dams or nuclear power plants. However, these changes are usually very small and do not significantly affect the length of a day.

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