Thread: Motor Quiz
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Unread 23-12-2011, 18:32
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Re: Motor Quiz

Quote:
Originally Posted by MooreteP View Post
Just try a small exercise:
Imagine that the motor may rotate 3701 revolutions in a single minute. Not an unreasonable possibility. Or even that the 60 oz-in is actually 60.01 oz-in. Recalculate your answers.
Every digit that you include beyond four becomes irrelevant, it is just calculator detritus.
Those are desired values, not measured values, and should not be considered when doing significant figures. It's assumed that Ether wants those values as close as possible.

Where significant figures should be applied is on the input values (In Aren's calculations the Free speed, Stall torque, and Spec voltage). All were given to at least 3 significant figures (It should be safe to assume that Spec Voltage wasn't 12v +/- 0.5, but rather +/-0.05 or even better).