Am i going about this angular acceleration question the right way?

AI Thread Summary
To find the average angular acceleration of a wristwatch's second hand, one must consider the hand's movement pattern. If the second hand moves smoothly, it maintains a constant velocity and has no angular acceleration. However, if the watch ticks and moves in increments, the second hand accelerates from rest to a certain angular velocity and then decelerates back to rest each second. The average angular acceleration can be calculated using the angular distance covered in each tick and the time taken. Understanding the type of movement is crucial for accurately solving the problem.
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Homework Statement


A 0.023 g 1.0 inch long second hand on a wristwatch. Find its average angular acceleration?


Homework Equations


av=w/t


The Attempt at a Solution



so would i just do 0.023 g divided by 1 minute?
 
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this is an oddly phrased question.

If the second hand goes around smoothly, it won't have any acceleration just a constant velocity.

If it's one of those watches that delivers an impulse every second then the hand would move 1/60th of 360 degrees every second. In this case you could use the angular version of the distance equation and solve for a, but you'd have to consider that the second hand goes from 0 to some alpha, then from that alpha back to zero (starting and stopping).

note: (alpha is angular acceleration)
 
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