And the reply is that you cant change the total angular momentum of the
system without reference to something external to said system (e.g. the
moon) so a windmill (or an RAR engine) working within the system can
take angular momentum from the earth (e.g. by spinning), but it will
give it back when it stops, and the earth will be spinning at the same
rate and will not have lost any angular momentum, so we wont have taken
any energy from it.
If the RAR system is getting energy from the rotation of the earth it is
doing something with the conservation of angular momentum that current
physics cannot explain, and I would not expect that to come from a
system consisting of 50 tons of ironmongery.
Nigel
On 09/02/2014 13:33, Nigel Dyer wrote:
The trade winds are driven primarily from the convection currents that
take their energy from solar heating. The corriolis force means that
the convection currents do not just go in a north-south direction but
swing to the east or west. Given all this, at least some of the
energy that drives a windmill sitting in the trade wind comes from
solar energy. I suspect that trying to work out what proportion (if
at all) comes from the spin of the earth is an interesting
maths/physics/engineering question.
I shall pass it to my son to look at.
Nigel
On 09/02/2014 06:41, Bob Cook wrote:
A better scheme to extract energy from the Coriolis force is the
spinning earth creates is to erect a windmill or your sailboat in the
trade winds which are caused by this effect.
Bob
