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<font face="Arial">At least some lamps last longer on AC than DC due
to ion migration.</font><br>
<br>
<div class="moz-cite-prefix">On 07/03/2015 04:51 AM, Dan Sheehan via
Stagecraft wrote:<br>
</div>
<blockquote
cite="mid:CAF5K5-WgWjy6BWq2gjy=5fafdYkSAm_KA5Um6S0354vRoEp+=g@mail.gmail.com"
type="cite">
<div dir="ltr">At the same nominal voltage, an incandescent lamp
will run
<div>equally bright on AC as on DC.</div>
<div><br>
</div>
<div>The AC nominal voltage is the root mean square of the
waveform;</div>
<div>the square root of the mean of the squares </div>
<div>of many infinitesimally small samples over a complete line
cycle.</div>
<div><br>
</div>
<div>squaring and then taking the square root makes it all
positive,</div>
<div>"mean" is like an average over the time of one complete
cycle...</div>
<div>which makes 120 VAC produce the same heating power in a
resistor as 120 VDC.</div>
<div class="gmail_extra">
<div class="gmail_quote"><br>
</div>
<div class="gmail_quote">HTH</div>
<div><br>
</div>
<br>
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</blockquote>
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<pre class="moz-signature" cols="72">--
Jerry Durand, Durand Interstellar, Inc. <a class="moz-txt-link-abbreviated" href="http://www.interstellar.com">www.interstellar.com</a>
tel: +1 408 356-3886, USA toll free: 1 866 356-3886
Skype: jerrydurand
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