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Physics help...sort of - Erebus - 2011-01-27
I kind of need help, but only because this problem looks to easy...
Because Earth’s rotation is gradually slowing, the length of each day increases: The day at the end of 1.0 century is 1.0ms longer then the day at the start of the century. In 20 centuries, what is the total of the daily increases in time.
It seems like it should be 20ms but... our problems have ranks and this is a rank 2 of 3 so I don't think it's that simple.
I've looked at other problems and the ranks for the most part seem to match the problems difficulty but this one seems off... only because it seems to easy and I think it's a trap...
Physics help...sort of - KajitiSouls - 2011-01-27
Uh... the only tricky thing I can think about this is that the delay per century is compounded. Typically the formula for this is F = P(1 + i)^n, where P is the current duration of a day, i is the % time increase per century at time 0, and n is the number of centuries.
Then there's the energy equation stuff, but I don't see how that would be different.
Frankly that's stupid imo. I think it's just 20 ms. But we could be wrong.
Physics help...sort of - Shidoshi - 2011-01-27
You don't know the slowing function of the earth's rotation. Your only way to guess is to suppose that it is linear at 1ms per century during all 20 centuries. It doesn't really make it compounded, it's not like the earth would get slower because it's slower (for it to be compounded).
What grade physics is this? How is this even physics anyway? There is nothing but math with a theme.
Physics help...sort of - Erebus - 2011-01-27
Shidoshi Wrote:You don't know the slowing function of the earth's rotation. Your only way to guess is to suppose that it is linear at 1ms per century during all 20 centuries. It doesn't really make it compounded, it's not like the earth would get slower because it's slower (for it to be compounded).
What grade physics is this? How is this even physics anyway? There is nothing but math with a theme.
Physics 1 College Level (It's like the first homework)
Physics help...sort of - 2147483647 - 2011-01-27
Oh my god, it's the answers!
http://www.monmsci.net/~fasano/phys1/Chapter_1_09.pdf
Gotta love Google.
Physics help...sort of - Shidoshi - 2011-01-27
Question is better formulated on the link. Should have passed us all that was written on it.
Physics help...sort of - OB3LISK - 2011-01-27
Wow I would have fucked that problem up so quickly. Dammit.
Physics help...sort of - Erebus - 2011-01-27
Shidoshi Wrote:Question is better formulated on the link. Should have passed us all that was written on it.
I copied the question word for word from the book >.>
Also thanks numbers.
Physics help...sort of - Shidoshi - 2011-01-27
Erebus Wrote:I copied the question word for word from the book >.>
Also thanks numbers.
Because Earth’s rotation is gradually slowing, the length of each day increases: The day
at the end of the 1.0 century is 1.0 ms longer than the day at the start of the century. In 20
centuries, what is the total of the daily increases in time (that is, the sum of the gain on the first
day, the gain on the second day)
From the PDF posted. There is that parenthesis which makes it pretty clear what it wants.
Physics help...sort of - Erebus - 2011-01-27
Shidoshi Wrote:Because Earth’s rotation is gradually slowing, the length of each day increases: The day
at the end of the 1.0 century is 1.0 ms longer than the day at the start of the century. In 20
centuries, what is the total of the daily increases in time (that is, the sum of the gain on the first
day, the gain on the second day)
From the PDF posted. There is that parenthesis which makes it pretty clear what it wants.
There is more then one science textbook in the world. The one i copied form is form mine. I'd gladly send you a pic if you wanted.
Physics help...sort of - Stereo - 2011-01-27
Seems like your version's asking the same question, just worded badly.
I'd go with the 2 hour~ response.
Physics help...sort of - modular - 2011-01-27
Looks like the link has the correct response...
Erebus Wrote:what is the total of the daily increases in time?
Careful... It's asking for the total extra time from each day after the starting point. Not for how much longer the day is after 20 centuries (but you do still need that). The link isn't worded any better, but since it tells you the answer you sort of automatically understand what it wants.