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Jan 26, 2020 at 9:50 vote accept user5539357
Jan 26, 2020 at 9:45 comment added user5539357 Yes, that's what I mean.
Jan 26, 2020 at 9:43 comment added my2cts Constrained motion means that the particle is held in circular orbit by an external force.
Jan 26, 2020 at 8:30 comment added user5539357 @my2cts could you explain the difference? Constrained circular motion means the particle orbits without a centripetal force?
Jan 26, 2020 at 7:38 answer added user249968 timeline score: 3
Jan 25, 2020 at 22:40 comment added my2cts I am unsure if you are thinking of a particle in constrained circular motion or of a free particle instead - as you imply that there is no external force.
Jan 25, 2020 at 22:06 comment added user5539357 Ok, does the velocity and therefore kinetic energy of the particle increase because when the radius is being reduced the velocity is not perpendicular to the force vector and it causes a change in the velocity of particle?
Jan 25, 2020 at 22:00 answer added MarkP timeline score: 0
Jan 25, 2020 at 21:27 history edited Qmechanic
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Jan 25, 2020 at 21:26 comment added user5539357 It spirals inwards, I guess its kinetic energy has to increase, and it explains why its linear velocity eventually doubles, but I don't really see why it changes because of spiraling.
Jan 25, 2020 at 21:12 comment added Bill N Circular motion requires a force directed toward the center, $F_c=mr\omega^2$. Also, think about the direction the particle moves as it is changing $r$ and whether work is done on the particle. Does the kinetic energy of the particle increase?
Jan 25, 2020 at 21:09 comment added user5539357 To maintain? I guess zero. To reduce the radius I have to apply a force that is perpendicular to the velocity vector, and it doesn't have to be an external force.
Jan 25, 2020 at 20:14 comment added Bill N Think about this: How much force is needed to maintain the original circular motion? Then, how do you reduce the radius to 0.5?
Jan 25, 2020 at 20:00 history asked user5539357 CC BY-SA 4.0