Solving Torque Unit Issue: kg*m3/s2 ≠ kg*m2/s2

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The discussion centers on a confusion regarding torque units, specifically the difference between kg*m3/s2 and kg*m2/s2. The correct torque formula is τ = Iα, where α represents angular acceleration, which is measured in rad/s². It is clarified that radians are dimensionless, allowing them to be eliminated from calculations. The misunderstanding arose from misinterpreting the formula sheet, leading to the initial confusion over the units. The resolution highlights the importance of correctly identifying angular acceleration in torque calculations.
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Homework Statement


Not really a homework question but a question about units that I can't figure out.

Homework Equations


Torque units = N*m
N=kg*m/s2
I units = kg*m2
a units = m/s2
Now my formula sheet says T=Ia

The Attempt at a Solution



torque=kg*m/s2*m=kg*m2/s2
Ia=kg*m2/s2*m/s2=kg*m3/s2
kg*m3/s2 in not equal to kg*m2/s2 What am I doing wrong?
Thanks for any help
 
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Chad Jensen said:
Now my formula sheet says T=Ia
It should say ##\tau = I \alpha## where ##\alpha## is the angular acceleration.
 
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Oh ok. That makes more sense. Thank you so, it is rad/s^2 which rads are considered dimensionless so they can be eliminated with no need to cross multiply or subtract to make them go away. You are then left with 1/s^2. Thank you I knew I was missing something simple. I looked at the formula sheet and it was alpha and not a
 

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