Angular and tangential acceleration

AI Thread Summary
The discussion focuses on calculating the tangential acceleration of a bug on the rim of a 78 rpm record with a diameter of 9.79 inches. The conversion of measurements is correctly noted, with the diameter converted to 0.248666 meters and the angular speed to 8.168 rad/s. The angular acceleration is calculated as 1.1668 rad/s² over a time of 7 seconds. A mistake is identified in the calculation where the diameter was mistakenly used instead of the radius, leading to an incorrect tangential acceleration result. The participants emphasize the importance of using the correct radius and rounding off to significant figures for accuracy.
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1. What is the tangential acceleration of a bug
on the rim of a 78 rpm record of diameter
9.79 in. if the record moves from rest to its
final angular speed in 7 s? The conversion
between inches and meters is 0.0254 m/in.
Answer in units of m/s2.



2. angular acceleration



3. converted 9.79 inches to 0.248666 meters using 0.0254 m/in. converted 78 rev/min to 8.168 rad/s using 2pi rad / 60 sec. alpha = delta omega / delta time. getting alpha as 8.168 rad/s / 7s = 1.1668 rad/s/s. multiply 1.1668 rad/s/s * 0.24866 m to get 0.2901 m/s^2. this is incorrect
 
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a = alpha*r

you are multiplying by the diameter 'd' which is twice the radius 'r'.
 
It looks OK, but you should round it off to 1 significant figure. Edit: But first heed rockfreak's advice:smile:
 
haha yeah i was multiplying by the diameter that's probably the issue
 
that confirms it, yall found my tiny mistakes once again...gracias amegos
 
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