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Name: Vincent
Status: student
Age: 20s
Location: N/A
Country: N/A
Date: 1999 


Question:
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.


Replies:
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.

Tim Mooney


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 mass.

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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