rotation doubt
we write rotational kinetic energy as 1/2Iw^2.So this moment of inertia is about the axis of rotation or about the centre of mass?
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@Gyro Gearloose
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thanks a lot
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moment of inertia is defined at a particular axis. that axis may not always be the c.o.m.
sir you know like while writing equations for a rigid body we usually consider everything about com (like com velocity or acln).Usually the axis of rotation is com and there is no problem with writing moi. But when the rotational axis is not about com there is a confusion
also @iTeachChem Helper bot is v cool
understood!
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Axis.
The center of mas can also be an axis in a given conditon (most of the time tbh)
but in general
its KE about the axis
If the point through which the axis passes itself has an translational velocity (let say a pen rotating about its center of mass and also moving forward horizontally)
then the total kinetic Energy of the pen will become
1*2 I w^2 + 1/2 mv^2
where v is the translational velocity of the point through which the axis passes (in this case, the center of mass)
This is a big blunder which I found while solving pyqs
Cuz most of the time center of mass is the axis
that was so clear tysm!
man i know right i keep finding new stuff every time i solve questions (also abj sir w)
A man of culture
+solved keshav
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+solved @Keshav
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