Calculate Rotational Velocity of Object Around Fixed Point

AI Thread Summary
To calculate the velocity of an object rotating around a fixed point, such as a clock hand, it's important to understand that the velocity varies with distance from the center. The linear velocity (v) increases proportionally with the radius (r), leading to the relationship where angular velocity (ν) is defined as ν = v/r. This angular velocity is consistent across all points on the rotating object and is measured in units of 1/s or radians per second. The arc length (a) can be integrated to find the angle (α) in radians, illustrating the connection between linear and angular measurements in rotational motion.
einsteinian77
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How could i calculate the velocity of an object rotated around a fixed point such as a hand on a clock. It seems as though each section of the hand would have a different velocity, the end part being the fastest while the beginning part being the slowest if not moving at all. I am guessing the velocity would be expressed in frequency somehow.
 
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Originally posted by einsteinian77
Im guessing the velocity would be expressed in frequency somehow.

That's correct, einsteinian77. Since the rotational velocity v increases proportional with radius r (distance from center), you define the angular velocity
[nu] = v/r.
This is the same for all points. The unit is 1/s. You could also say it's radians per second, since by integrating you get the angle:
[alpha] = a/r
where a is the arc length, and [alpha] is measured in radians.
 
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