String tension with an attached whirling mass

AI Thread Summary
A 0.40 kg mass attached to a 0.75 m string is being analyzed for maximum speed without breaking the string, which can withstand a maximum tension of 450 N. The discussion emphasizes the need to calculate centripetal acceleration, as the force acting on the mass is directed inward while it moves in a circular path. Key equations include the centripetal acceleration formula, a_c = v²/r, and the relationship between angular velocity and radius. The participant expresses confusion about how to relate linear and angular acceleration in this context. Understanding these concepts is crucial for determining the maximum speed of the mass.
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Homework Statement


A 0.40 kg mass, attached to the end of a .75 m string, is whirled around in a circular horizontal path. If the maximum tension that the string can withstand is 450 N, then what maximum speed can the mass have if the string is not to break?


Homework Equations


F=m*a
T=r*F*sin(theta)
v=r*omega

The Attempt at a Solution


I have absolutely no idea where to even begin with this. My idea was to find the acceleration when the force is 450 N, but that yields the linear acceleration not the angular one which does nothing for me. I am stumped.
 
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Well even with the object being swung around at a constant (angular) speed you will still have a force. Because the direction of the velocity vector is changing, and acceleration is change in velocity. So you are looking for the acceleration inward, which is the centripetal acceleration, the force vector would be pointing from the object toward the center of the circle as it spins.

So the equations you are missing are:
a_{centripetal}=\frac{v^{2}}{r}
OR equivalently:
a_{centripetal}=\omega^{2}r
 
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