Calculating Angular Acceleration w/ Torque & Moment of Inertia

AI Thread Summary
Torque and moment of inertia are critical for calculating angular acceleration using the formula α = τ/I, where τ is torque and I is moment of inertia. In the example provided, with torque at 12 kg m²/s² and moment of inertia at 3.00 kg m², the resulting angular acceleration is 4 rad/s². The discussion highlights that radians are considered a dimensionless unit, which helps categorize quantities as angular. This distinction is important for clarity in physics calculations involving rotational motion. Understanding these concepts is essential for solving related problems effectively.
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Homework Statement



this is a question just to help with my understanding: ...

when Torque (kg m^2/s^2) and the Moment of Inertia (kg m^2) are known and used to find angular acceleration, ... T(net)/I, are the units for the resulting acceleration rad/s^2

Thanks :-)

Homework Equations


##\tau = I \alpha##

The Attempt at a Solution


[/B] Example:
t = 12 kg m^2/s^2
I = 3.00 kg m^2

angular acceleration = torque/I = 12 kg m^2/s^2 / 3.00 kg m^2 = 4 units(?) / s^2
 
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Yes. Angular acceleration is given in radians per second squared ##(rad/s^2)##.

The radian is sort of a "unitless unit" that appears and disappears as required when working with angular quantities. It's based on a ratio of lengths from the unit circle, where an angle is defined via the arclength along the circle divided by the radius length. It serves to distinguish a quantity as being angular in nature.
 
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thank you! :-)
 
gneill said:
unitless unit
How about "dimensionless unit"?
 
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haruspex said:
How about "dimensionless unit"?
Sure! That's probably better nomenclature. :smile:
 
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