Stresses in a rotating object?

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In summary, the conversation discusses the idea of a rotating disc reaching the speed of light and the implications of this. The suggestion is made to refer to a physics FAQ on the topic for further clarification.
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billyboy
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Has anyone considered the following. If I have a really big disc and rotate it at a certain angular velocity. Then at some distance from the centre the tangential speed of the disc will equal the speed of light and any distance beyond will have a speed greater than that of light. Obviously this cannot be the case and some strange time dilation and length contraction effects will take place. Can anyone explain exactly what does happen? Presumably some stresses are set up in the disc which could be calculated?
 
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Related to Stresses in a rotating object?

1. What causes stresses in a rotating object?

Stresses in a rotating object are caused by the centrifugal force acting on the object as it rotates. This force pulls the object outward, creating tension and stress on the object's surface.

2. How do you calculate stresses in a rotating object?

The equation for calculating stresses in a rotating object is σ = ρω²r, where σ is the stress, ρ is the density of the object, ω is the angular velocity, and r is the distance from the center of rotation. This equation is known as the Euler-Cauchy formula.

3. What types of stresses can occur in a rotating object?

The main types of stresses that can occur in a rotating object are tensile stress, compressive stress, and shear stress. Tensile stress occurs when the object is being pulled apart, compressive stress occurs when the object is being squeezed together, and shear stress occurs when the object is being twisted.

4. How can stresses in a rotating object be reduced?

Stresses in a rotating object can be reduced by increasing the object's diameter, reducing the object's rotational speed, or changing the material of the object to one with a higher strength-to-weight ratio. Additionally, proper design and balancing of the rotating object can also help to reduce stresses.

5. What are the potential consequences of high stresses in a rotating object?

High stresses in a rotating object can lead to structural failure, resulting in damage to the object and potential harm to individuals nearby. It can also cause excessive wear and tear on the object, leading to a shorter lifespan and increased maintenance costs.

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