document.write( "Question 697149: The potential difference across a circuit is given by the complex number\r
\n" ); document.write( "\n" ); document.write( "V = 40 + j35 volts\r
\n" ); document.write( "\n" ); document.write( "and the current is given by the complex number\r
\n" ); document.write( "\n" ); document.write( "I = 6 + j3 amps\r
\n" ); document.write( "\n" ); document.write( "a) sketch the appropriate phasors on an Argand diagram.\r
\n" ); document.write( "\n" ); document.write( "b) find the phase difference (i.e. the angle Φ )between the phasors for voltage \r
\n" ); document.write( "\n" ); document.write( " V and the current I.\r
\n" ); document.write( "\n" ); document.write( "c) Find the power (watts) given that P = V x I x cos Φ
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Algebra.Com's Answer #430081 by KMST(5328)\"\" \"About 
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V = 40 + j35 volts and I = 6 + j3 amps
\n" ); document.write( "a) sketch the appropriate phasors on an Argand diagram.
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\n" ); document.write( "b) find the phase difference
\n" ); document.write( "The angle \"alpha\" between the voltage V and the real, x-axis can be found from
\n" ); document.write( "\"tan%28alpha%29=35%2F40=0.875\" --> \"alpha+=+0.71883\" radians (rounded)
\n" ); document.write( "The angle \"beta\" between the current I and the real, x-axis can be found from
\n" ); document.write( "\"tan%28beta%29=3%2F6=0.5\" --> \"beta+=+0.46365\" radians (rounded)
\n" ); document.write( "We can calculate very close approximations of \"phi\" and \"cos%28phi%29\"
\n" ); document.write( "\"phi=alpha-beta=0.71883-0.46365=0.25518\" radians (approx \"14.6%5Eo\" in degrees)
\n" ); document.write( "\"cos%28phi%29=cos%280.25518%29=0.9676\" (rounded)
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\n" ); document.write( "c) Find the power (watts) given that P = V x I x cos Φ
\n" ); document.write( "The magnitudes of V and I are
\n" ); document.write( "\"V=sqrt%2840%5E2%2B35%5E2%29=53.151\" (rounded)
\n" ); document.write( "\"I=sqrt%286%5E2%2B3%5E2%29=6.7082\" (rounded)
\n" ); document.write( "\"P=V%2AI%2Acos%28phi%29=53.151%2A6.7082%2A0.9676=highlight%28345%29\"watt
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