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single phase C question

eurotrotter · 2005-06-28 07:48:35

im doing a prolem at the moment and in the solution, it is determined from the cos of fie that the current is lagging the voltage cos fie was equeal to 0.705 how could he tell from this that is was lagging?

28-06-2005 8:48am

#1

eurotrotter

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im doing a prolem at the moment
and in the solution, it is determined from the cos of fie that the current is lagging the voltage
cos fie was equeal to 0.705
how could he tell from this that is was lagging?

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Comments

#2 28-06-2005 12:35pm

Molly

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As far as i can remember

Positive cos of phi = voltage leading, current lagging
Negative cos of phi = current leading, voltage lagging

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#3 28-06-2005 1:13pm

eurotrotter

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Molly wrote:

As far as i can remember

Positive cos of phi = voltage leading, current lagging
Negative cos of phi = current leading, voltage lagging

ya i think your rite there bud
thanks

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#4 01-07-2005 2:11pm

SparkyLarks

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the cos of 20 degrees positive or negative will be positive.

If phi is positive the Voltage is leading
If phi negative Voltage is lagging

I think
you just know from the x+jy form

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