A simple angular velocity with two spheres problem

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SUMMARY

The discussion centers on the dynamics of two masses tied by a string within a rotating hollow cylinder. The key equation provided is T = mrω², where T represents tension, m is mass, r is the radius, and ω is angular speed. The confusion arises regarding whether the tension should be considered as T = mrω² for each mass or T = 2mrω² due to the presence of two masses. It is established that the tension in the string is equal to mrω², not doubled, as each mass independently exerts tension on the string.

PREREQUISITES
  • Understanding of angular velocity and its implications in rotational dynamics.
  • Familiarity with Newton's laws of motion, particularly regarding tension in strings.
  • Basic knowledge of circular motion and the relationship between mass, radius, and angular speed.
  • Ability to apply fundamental equations of motion in a rotational context.
NEXT STEPS
  • Study the principles of rotational dynamics in detail, focusing on tension and forces in rotating systems.
  • Learn about the effects of angular acceleration on tension in strings and ropes.
  • Explore examples of tension in various mechanical systems, including pulleys and springs.
  • Investigate the implications of multiple masses in rotational systems and how they affect tension calculations.
USEFUL FOR

Physics students, mechanical engineers, and anyone studying dynamics in rotational systems will benefit from this discussion, particularly those tackling problems involving tension in rotating bodies.

dennislam
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Homework Statement


Two masses have same mass m, both of them are tied by a string and put in a hollow cylinder.
When the cylinder start to rotate until the angular speed is ω.
The tension in the string is T and the string breaks, both masses move away from the axis in the hollow cylinder.

XRuP0Nw.png


Homework Equations


T=mrω^2

The Attempt at a Solution


I have no idea about whether the tension T is equal to mrω^2 or 2mrω^2 (since there is two masses)
Please help!:cry:
sorry for my bad english
 
Physics news on Phys.org
If you pull a spring with a force F, the spring pulls back with a force F. The tension in the spring is F, not 2F.
Same with a rope. In the situation described, but e.g. also if the rope hangs over a pulley and the two masses both pull down with ##mg##. Tension is ##mg##, not ##2mg##
 

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