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*From*: Brian Whatcott <betwys1@sbcglobal.net>*Date*: Mon, 12 Jan 2009 19:54:14 -0600

I wrote earlier:

I calculated the input power to produce this result as 91 watts into 176.3 g. water. The wattmeter was indicating 84 watts for this. Checking the heaters, I reada resistance of 195 ohms, and the input voltage 121 V.This should have provided a heating rate of 75 watts. This complete lack of agreement put a stop to the next phase...So much for the joys of H.S. experimental procedure.....I finally twigged the problem, though I had not provided enough clues for you to easily guess what

it was. I noticed that the connecting wires for the heating resistors were discolored.

I coated the bare wires with epoxy, and tried again with distilled water.

This time the least squares straight line was 0.12028 deg per second into 150.0 gm water.

This provided a heating input estimate of 75.4 watts

The wattmeter indicated 73 watts and the Vsq/R amounted to 74 watts.

Much more the discepancy you might expect....

I had not accounted for the electrolytic heating before.

Ho hum....

BrianW

**References**:**Re: [Phys-l] glassware needed***From:*Brian Whatcott <betwys1@sbcglobal.net>

**Re: [Phys-l] glassware needed***From:*Bernard Cleyet <bernardcleyet@redshift.com>

**Re: [Phys-l] glassware needed***From:*Brian Whatcott <betwys1@sbcglobal.net>

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