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Old 04-20-2019, 03:16 AM
bistander bistander is online now
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Originally Posted by BroMikey View Post
Let's put it like this. Does anyone know the input power in the video?
At time marker 13:15, input power is 48.84 watts from voltmeter and ammeter on the batteries.

There is no load on the motor shaft so output power is necessarily zero.

Then efficiency at the 900 RPM constant speed (which he measured) is output power / input power * 100% which is 0 watts output / 48.84 watts input * 100% = 0% efficient.

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