Need Help!- Step Motor Rotor Inertia Units

[mcArch]

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I have a motor, the literature of which lists the rotor inertia as 4.4oz/in^2. The motor sizing/system calculating software I'm using has the rotor inertia in units of in-lb-s^2. and shows a reflected inertia to motor of 0.011222939in-lb-s^2. It indicates that rotor inertia of the motor must be at least 1/6 the reflected inertia. Does anyone know what the relationship of those units are, or how to get from the oz/in^2 to in-lb-s^2?

Thanks in advance for any help

--Mike

[Al_The_Man]

There are many on-line conversion calculators.
Al.

[mcArch]

Thanks Al, I found this one:
http://www.magtrol.com/support/inertia_calc.htm
At first, I wondered whether there was a typo in the product lit. & did not realize that there may be several different units for the same variable, eg: speed is dist/time & I thought that inertia would be the same simple concept, I must review my physics there.

Thanks again.