Re:World Energy Hits a Turning Point: Solar That's Cheaper T...
by logicallee on Friday December 16, 2016 @02:54AM
(#13191778)
>but we're talking 10^7 kg, not 10^25 kg
which, let's not forget, is still 10,000,000 kg!
But it gets worse. The thing I quoted, which generates 150 lbs of magnetism -- only weighs 0.3 ounces!! (0.01875 lbs or 0.0085 kg).
were your figures for 150 lbs or for 0.018 lbs of gravitational force from a point source? :)
What I wanted to convey was that if you could get the mass closer to the object, you wouldn't need anywhere near 5.972 × 10^24 kg anymore. For instance, if you had a sphere whose center of mass was 1 m from your test object, and wanted it to exert the same force that the Earth exerts 6.7 x 10^6 meters from the object, you would only need your sphere to have a mass of 1.33 x 10^11 kg.
If we were using a sphere small enough that we could get its center of mass 10 mm from our test object's center of mass, it would only a mass of 1.33 x 10^7 kg.
So, the magnet is still winning in the sense that it still takes a lot of mass to counter the magnet, but we're talking 10^7 kg, not 10^25 kg.