Quote:
Originally Posted by YourSurrogateGod
Is it a German built motorbike?
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Quote:
Originally Posted by YourSurrogateGod
Is it a German built motorbike?
An encrypting method used by some native americans, based on the singing rithm of the frogs of a particular river.
I be dmm... :ehh:Quote:
Originally Posted by DeepButi
I remember hearing the word a while ago, I don't remember what it means. I figured that some of you gents would know.Quote:
Originally Posted by Deniz
Someone should ask a question and resurect this thread.
Okay here's one. How much would the earth's rotation have to increase for the people to float in the air? Assume you are at the equator and gravity is 9.8 meters/sec. A teacher told her second grade students (my neice) this was possible. Give an aproximate answer so ignore things like air friction and stuff like that. So what I'm saying is keep it simple.
-Ben
Assumes:
Earth Radius: 6,378 km
Equatorial circumference: 40,000 km
Rotation speed: 40,000 / 24 h = 1670 km/h = 464 m/s
Centrifugal force: Fc = mv^2/R
Gravity force: G = mg
To begin fly Fc must (at least) equal G.
Thus: mv^2/R = mg
v = sqrt(gR);
v = 7910 m/s = 25884 km/h
To make you float in the air, the earth rotation speed must increase 17 times.
Unfortunatelly for you, Earth rotation speed is actually decreasing. That makes the day longer (than 24 hours) and the year shorter (that 365 days).
Please look here Be sure to read the full thread.
What's your point? I'm not following... :confused:
All my life's a circle....
It seems like we've been here before
I can't rmember when (oh yes I can)
But i've got this funny feeling that we'll all be together again....
But if you're floating, then there's no static friction to pull you around with the Earth... meaning you'll stop orbiting... meaning you'll fall to the Earth... meaning friction will pull you back to orbiting velocity... meaning... I've got a headache...
Some people don't need to move at all....
I'm sorry if this question was asked before. I'm not really up to rereading the whole thread each time I have a question to make sure it was asked before.
As for the answer I did it a little differently. I'm not sure which is right but here's how I did it.
The radius of the earth is 6378 km. Ahh I found my problem. I'll make it in red and contiune with my answer even though it's wrong. For you to float (basically be in orbit) you need to displace as much distance as you fall each second. So I made a right triangle. The hypotinus(sp?) is 6378km and one side is 6378km - .0098km (the distance you fall in one second). Calcing the last isde you get 11.18 km. So you need to travell that far is one sec. So 11180 m/sec - 461m/sec(current velocity not sure where I found that either) you get and increase of 10719 m/sec is need to float.
So I messed up with how much a person falls in one second. If I change that to what it should be 4.9 m then the answer I get is 7906 m/sec which is basically the same as yours. Good job.
So what's the next question?
-Ben
I have no idea whatsoever if this question was asked and answered before.
You told me to use the KISS principle. (Kepp It Simple, Stupid). So I did. I don't understand your calculations with 1 second fall, etc. When you fly you don't fall and fly again. :D
I will come with a question tomorrow.
/Physics laws must have mathematical beauty.
The idea is the same as how something stays in orbit. It is always falling to earth but it stays in orbit because it is moving in a direction perpendicular to gravity. So in one second something falls to the earth 4.9 meters assuming gravity at 9.8 m/sec. So that forms the right triangle and using a*a + b*b = c*c you get the horizontal side as 7906 meters. Since the earth is so close to flat I just say the earth needs to rotated that much.
See attached picture. I hope that helps.
I think your way is better though.
-Ben