ORIGINAL: davidhand
It will move in the direction the jet is pushing but slowly. Newton's law is in effect but the turbine thrust is partially cancelled out by the air hitting the sail, again Newton's law. If 100% of the energy of the air hitting the sail was converted into thrust the thing would stand still. However there will be losses so it will move in the durection the jet is pushing but more slowly.
David gets my vote !!! I agree. I do understand Newtons law of action and equal and opposite reaction, but the two actions are not equal.... there is a loss of thrust in the air between the exhaust nozzle and the sail. Therfore the Turbine will prevail and the skateboard will move in the direction that the turbine is wanting to move it. not the sail.
That's all I got to say about that !!
Dr. Danno
Astrophysicist, Genius, Astronaut, Test Pilot, Aerospace Engineer, and part time Brain Surgeon !!![X(]