# Is this Perpetual Motion Machine generating energy from nothing ?

Discussion in 'Physics & Math' started by Singularity, May 29, 2006.

1. ### Janus58Valued Senior Member

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2,297
Exactly what point are you trying to make with this comment? Yes, man-made satellites would undergo like effects. Of course we have no satellites designed to orbit the Earth slower than it rotates, so these effects would not cause them to climb to higher orbits but ot drop to lower ones. The exception are the geosationary satellites which orbit at the with the same period as the Earth rotates, so are already tidally locked, and no more effect is felt. The thing with man-mafde satellites however is that they are very small and naturally have a very weak tidal interaction with the Earth. the coresponding cahnge in orbit would be very small. But let's say that the cahnge in orbital radius is the same as the moon's, 4cm/yr. For a LEO satellite that would equate to an orbital change of 40 cm over 10 yrs, which would result in a change in its period of .0005 sec. Considering all the other things effecting a stellites orbit,(the Moon tugging on it, solar activity expanding the atmosphere thus increasing drag, etc.) said effect would be most likely swamped out.
So, unless you have some actual evidence showing that man-made satellites are not effected at all by tidal interaction, you are just talking out of your hat here.
Again, it is because the tidal bulge does not line up exactly with the moon and leads it a bit, some of this "pull" tugs the moon forward in its orbit. This is called "tidal torque.

This increases the Moon's orbital energy.

Orbital energy of the moon can be expressed by

E = mv²/2- GMm/r

and its orbital velocity is (we'll assume a circular orbit for simplicity here)

v=sqrt(GM/r)

by substituting for v in the first equation we end up with.

E = -GMm/2r
(you get the same expression with an eliptical orbit, only we replace r with a for the semi-major axis or average orbital radius. )

Note that as r increases E becomes greater (less negative. in orbital mechanics, zero orbital energy is for an object at rest WRT and an infinite distance from the body it is orbting WRT.) Conversely, if you increase the energy, r must increase in response.

Thus if you push (or pull) an orbiting object forward in the direction of its orbit, you increase its energy, and force it to climb into a higher orbit. and from the expression for orbital velocity we see that a higher orbit is a slower orbit.

For a more detailed examination of tidal torque, see here:

http://scienceworld.wolfram.com/physics/TidalTorque.html

3. ### CANGASRegistered Senior Member

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1,612
Singularity is just pretending to be intentionally dense. It is Sing's happy game. If Sing really disagrees with the orbital mechanics arguement presented by multiple parties then Sing should present specific logical or mathematical or both arguements why the energy transfer mechanism is incorrect.

5. ### Billy TUse Sugar Cane Alcohol car FuelValued Senior Member

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23,198

"How zero-exhaust rocket to the stars works."