Acceleration of Center of Mass

AI Thread Summary
The discussion centers on a model involving two slender rods connected at a pin, with a focus on determining the acceleration of the center of mass of link OA as the angle theta changes. It is clarified that even with a constant angular velocity, the center of mass does not have zero acceleration due to its circular motion. The user seeks clarification on the variables involved, specifically the definitions of theta, the horizontal slider, and alpha. There is confusion regarding the dimensionality of the variables and the distinction between linear and angular acceleration. The conversation emphasizes the importance of clear variable definitions in physics problems to facilitate understanding.
Ian Blankenship
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Thread moved from the technical forums, so no Homework Template is shown
I have a model of two slender rods (call them OA and AB) connected with a pin at A, anchored at O with a pin, and attached to horizontal slider at B. I am supposed to show graphs of different variables in Matlab as the angle theta changes. One of these steps is to show the acceleration of the center of mass of link OA. It is given that link OA has a constant angular velocity 'omega' in the CW direction. Dumb question, but if the rod has constant angular velocity, would a point half way down this link (center of mass) also have zero acceleration? (Note, I am asked to find linear acceleration, i.e. a=alpha/r)
 
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Likes Lakshit
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Can you draw a diagram or something? It's not clear what theta is, and what a horizontal slider is, and what alpha is.
 
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Likes Lakshit
Apologies, here is an image of the problem.
dynamicsdiagram.PNG


This is the same image as what is used in my problem, except that T direction (torque I assume) is placed on this diagram.
 
This should be in the homework forum.
 
Ian Blankenship said:
Note, I am asked to find linear acceleration, i.e. a=alpha/r
Note: this looks utterly wrong, dimensionally. Unless you tell us that alpha is the acceleration and a the angular acceleration. That's what 's so useful about the template in the homework fora: people can understand what you type if you explain the variable names.

And: something that moves in a circle does not have zero acceleration (Newton 1).
 
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