document.write( "Question 1026264: The formula T = 2π√(l/g) relates a pendulum's period, T, in seconds (the time it takes to swing back and forth) to its length, l, in centimeters using g, the gravitational acceleration of 981 cm/sec^2.\r
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\n" ); document.write( "\n" ); document.write( "√(l/g) means square root of l/g
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Algebra.Com's Answer #641498 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
the formula is \"T+=+2+%2A+pi+%2A+sqrt%28L%2Fg%29\".\r
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\n" ); document.write( "\n" ); document.write( "i use capital L because it's less easy to be confused with the number one.\r
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\n" ); document.write( "\n" ); document.write( "what you need to do is solve this equation for L.\r
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\n" ); document.write( "\n" ); document.write( "the given period is T.\r
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\n" ); document.write( "\n" ); document.write( "start with \"T+=+2+%2A+pi+%2A+sqrt%28L%2Fg%29\".\r
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\n" ); document.write( "\n" ); document.write( "divide both sides of this equation by (2 * pi) to get:\r
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\n" ); document.write( "\n" ); document.write( "\"T+%2F+%282+%2A+pi%29+=+sqrt%28L%2Fg%29\".\r
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\n" ); document.write( "\n" ); document.write( "square both sides of this equation to get:\r
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\n" ); document.write( "\n" ); document.write( "\"%28T%2F%282%2Api%29%29%5E2+=+L%2Fg\".\r
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\n" ); document.write( "\n" ); document.write( "multiply both sides of this equation to get:\r
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\n" ); document.write( "\n" ); document.write( "\"g%2A%28T%2F%282%2Api%29%29%5E2+=+L\"\r
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\n" ); document.write( "\n" ); document.write( "that's your answer.\r
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\n" ); document.write( "\n" ); document.write( "\"L+=+g%2A%28T%2F%282pi%29%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "for example, if the given period is 5 seconds, then the formula would becomes:\r
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\n" ); document.write( "\n" ); document.write( "\"5+=+2+%2A+pi+%2A+sqrt%28L%2Fg%29\".\r
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\n" ); document.write( "\n" ); document.write( "you would solve for L to get:\r
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\n" ); document.write( "\n" ); document.write( "\"L+=+g%2A%285%2F%282pi%29%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "since g = 981, the formula would become:\r
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\n" ); document.write( "\n" ); document.write( "\"L+=+981%2A%285%2F%282pi%29%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "this results in L = 621.2255072 centimeters.\r
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\n" ); document.write( "\n" ); document.write( "if you go back to the original formula, then it becomes:\r
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\n" ); document.write( "\n" ); document.write( "\"T+=+2+%2A+pi+%2A+sqrt%28621.255072%2F981%29\".\r
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\n" ); document.write( "\n" ); document.write( "that results in T = 5.\r
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\n" ); document.write( "\n" ); document.write( "any discrepancy will be due to rounding.\r
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\n" ); document.write( "\n" ); document.write( "i used internally stored numbers and the answer came exactly to 5.\r
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\n" ); document.write( "\n" ); document.write( "the number of 621.255072 that you see has been rounded to the number of digits that the calculator can display.\r
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\n" ); document.write( "\n" ); document.write( "using that only will give you an answer that is close to 5, but not right on.\r
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