On Wed, 2008-05-21 at 20:47 -0700, Pat McBride wrote: > Daniel, are you serious?????????? Last time I checked, the attraction of a > body to the earth -mass- by the force of gravity is pretty well constant. > There may be variations around the earth, but they are probably minor.
About 1 or 2 parts in 1000 I think. However, the spin of the earth provides kinetic energy for objects on its surface and those at the equator are travelling fastest so launching them in the right direction makes it easier to get off the planet because they already have some of the energy they need to escape from the Earth's gravitational field. Circumference of the earth is about 25,000 miles and it takes 24 hours so objects at the equator are travelling at a bit over 1000 miles per hour. If we could switch off gravity all those object would fly off into space at more than 1000 mph tangential to the equator. Of course we would also lose the atmosphere too*. Escape velocity is about 25,000 mph neglecting air resistance. So a 1000 mph boost will help - not that much but probably enough to make it better economics to launch at the equator :-) > A suggestion -- when you have breakfast next, drop a slice of buttered toast > on the floor. Weigh the toast before dropping, and record the weight > divided by the force of gravity where you are. This will give you it's > mass. Weight divided by acceleration of gravity, the force of gravity is the weight so if you divide weight by force of gravity at any point you will always get 1 (neglecting quantum effects for very tiny objects) > Then drop the toast on the floor. Record the time it takes for about > 20 trials, also recording the number of times it lands butter side up. This > will approximate the level of frustration of anyone having breakfast with > you (wife, mother, girlfriend, dog, etc.) :-) Usually butter side down I believe. More so if it has something sticky like maple syrup on it :-) > If you have any dogs such as my two, the recovery rate by the dog can be > measured in milliseconds. I therefore suggest that you restrain any and all > pets, spouses, relatives, and so on while conducting the experiment. > > LOL, LOL > > Pat McBride * The reason the atmosphere is composed as it is is partly because of gravity. Light atoms like hydrogen and helium at Earth temperatures go fast enough to escape, Nitrogen and Oxygen are slower so stay captured. So for life as we know it you need a planet not only the right distance from a similar star to the Sun but also one that has the right density to have the gravity to get the atmospheric composition right. Hell of a coincidence but given the number of stars not implausible. Just might have a long look to find anything similar within contact distance. Or indeed with a civilisation that is at a similar stage in its development. If it's 100 years behind us they aren't going to be able to interpret any signals. 100 yeas ahead and they might have destroyed themselves :-) Ian -- New QCA Accredited IT Qualifications www.theINGOTs.org You have received this email from the following company: The Learning Machine Limited, Reg Office, 36 Ashby Road, Tamworth, Staffordshire, B79 8AQ. Reg No: 05560797, Registered in England and Wales. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
