Torque from a frame of reference

AI Thread Summary
Defining torque from a frame of reference does require the frame to be inertial for the standard equation ##\vec \tau = I\vec\alpha## to hold true. In a non-inertial frame, such as an accelerating car, pseudo forces must be considered, complicating the torque calculations. For example, while sitting in an accelerating car, the torque needed to maintain balance is influenced by the acceleration of the frame. Therefore, when analyzing torque in non-inertial frames, adjustments must be made to account for these pseudo forces. Understanding this distinction is crucial for accurate torque analysis in varying frames of reference.
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Whenever we define torque from a frame of reference, is it necessary for the frame to be inertial?
Please explain because I am unclear on this.
 
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Yes. In e.g. an accelerating frame of reference you no longer have ##\vec \tau = I\vec\alpha##.
Example: you sit in an accelerating car and have to lean forward to stay sitting upright. ##\alpha## of your head w.r.t. your hips is zero but you (or the backrest) do have to exercise a torque to stay with your head above your hips.
 
In case of non inertial frame, a pseudo force should be taken and then we can proceed writing the torque. Right?
 
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