document.write( "Question 65557: I am not good with word problems so can someone help?\r
\n" ); document.write( "\n" ); document.write( "The electrical resistance R of a wire varies as its length L and inversely as the sqaure of its diameter. A wire 20 meters long and 0.6 centimeters in diameter made from a certain alloy has a rsistance of 36 ohms. What is the resistance of a piece of wire 60 meters long and 1.2 centimeters in diameter made from the same material?\r
\n" ); document.write( "\n" ); document.write( "Ok so I analyzed the problem and I know that the key words here are: \r
\n" ); document.write( "\n" ); document.write( "Resistance varies directly in length and inversely as the square of it's diameter\r
\n" ); document.write( "\n" ); document.write( "36 ohms=20 meters long and .6 in diamter
\n" ); document.write( "? ohms=60 meters long and 1.2 in diameter\r
\n" ); document.write( "\n" ); document.write( "Both have same material.\r
\n" ); document.write( "\n" ); document.write( "We are trying to find resistance to the second set of numbers. \n" ); document.write( "

Algebra.Com's Answer #46120 by 303795(602) $\"\"$ $\"About$

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The resistance varies directly with length so the second wire is 3 times as long so it will have 3 times the resistance 36 * 3 = 108 ohms. This assumes the second wire has the same diameter but it doesn't.
\n" ); document.write( "The resistance varies as the inverse of the square of the diameter. The second wire is twice the diameter of the first. Square 2 to get 4. The inverse of 4 is 1/4 so the resistance will be 1/4 of 108 ohms = 27 ohms. \n" ); document.write( "

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