If a bead is placed on a rod and rotated...

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SUMMARY

The discussion centers on the dynamics of a bead placed on a rod with a coefficient of friction, specifically analyzing the conditions under which the bead begins to move when the rod is rotated with an angular velocity. The key point is that, despite the absence of gravity, the normal force arises from the friction between the bead and the rod due to the snug fit of the bead's hole around the rod. This frictional force is essential for the bead to accelerate along the rod, contradicting the initial assumption that it would fly off instantly.

PREREQUISITES
  • Understanding of rotational motion and angular velocity
  • Knowledge of frictional forces and coefficients of friction
  • Familiarity with normal force concepts in non-gravitational environments
  • Basic principles of dynamics in a frictional context
NEXT STEPS
  • Study the effects of friction in rotational systems
  • Explore dynamics in microgravity environments
  • Learn about the mathematical modeling of frictional forces
  • Investigate the role of normal force in various physical scenarios
USEFUL FOR

Physics students, mechanical engineers, and anyone interested in the principles of motion and friction in rotational systems.

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Homework Statement


A bead is placed on a rod with coefficient of friction m, it's accelerated from rest with angular velocity a, find the time it takes to start moving. Neglect gravity

Homework Equations


Force of friction =Nm

The Attempt at a Solution


They said there's no gravity, so i don't quite see where the normal force is coming from so it'd fly off instantly. Well this is the wrong answer, where the heck is the normal force coming from? If i do this in space, id expect the rod to just move on without doing anything bc it's actually not pressing against anything
 
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Its a bead on the rod. The bead has a hole in it and the rod passes through the hole snugly hence there's friction when it moves. Some force causes it to accelerate.
 
jedishrfu said:
Its a bead on the rod. The bead has a hole in it and the rod passes through the hole snugly hence there's friction when it moves. Some force causes it to accelerate.

Oh thanks, i thought it was a bead on top of a road : 7.
 

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