If you have one gyroscope with its rotating mass parellel
to the force of gravity, it will stay in that position. Now, if you
rotate that gyroscope, keeping the position constant, say you spin in a
circle. depending on which way you spin, the gyroscope will either feel
as if it is pulling toward the ground or the sky. I was wondering if you
mounted two gyroscopes on a center axis, with their rotating masses
parellel to the axis and the force of gravity, and then rotated them
around the center axis would you acheive a force opposite to that of
gravity. If so, why, and will it every be greater than gravity.
No. Rotating a spinning gyroscope as you describe does not produce a
force, but rather a torque about the center of mass. The net force on
the center of mass from a torque is zero.
A gyroscope does not do respond in any unusual way to a force trying to push
it as a mass. It only acts strange when a torque is applied, that is, a
force that tries to change its angular monentum. A gyroscope dropped from a
height will just fall. The apparent feeling that a gyroscope is "pulling
toward the ground or the sky" is a misconception; the gyroscope is actually
trying to rotate about its own center of mass, not to move its center of
I don't understand exactly what arrangement of gyroscopes you are proposing,
because when you describe "rotating masses parallel to the axis and the
force of gravity" I can't tell if you mean their axes of rotation are
perpendicular to the ground or what. However, I can say, with great
confidence, that nothing you do with spinning these gyroscopes is going to
make them rise up off the ground. To do that, you need to push them upward,
just like any other load.
Richard E. Barrans Jr., Ph.D.
Assistant Director, PG Research Foundation
Darien, IL USA
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Update: June 2012