document.write( "Question 1178647: The formula F=Kq1q2/r^2 gives the force between two point charges of q1 and q2 coulombs that are r metres apart. If two equally charged balls are placed 0.1m apart and the force between the balls is 9.8*10^-4 Newtons, calculate the charge on each ball to 2 significant figures, given K=9.0*10^9. \n" ); document.write( "
Algebra.Com's Answer #853636 by ikleyn(53617)\"\" \"About 
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\n" ); document.write( "The formula F=Kq1q2/r^2 gives the force between two point charges of q1 and q2 coulombs that are r metres apart.
\n" ); document.write( "If two equally charged balls are placed 0.1m apart and the force between the balls is 9.8*10^-4 Newtons,
\n" ); document.write( "calculate the charge on each ball to 2 significant figures, given K=9.0*10^9.
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\n" ); document.write( "\n" ); document.write( "        Calculations in the post by @mananth are incorrect.\r
\n" ); document.write( "\n" ); document.write( "        I came to bring a correct solution.\r
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document.write( "F = \"K%2A%28%28q1%2Aq2%29%2Fr%5E2%29\"\r\n" );
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document.write( "r = 0.1\r\n" );
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document.write( "F = 9.8*10^-4 Newtons,\r\n" );
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document.write( "K = 9.0*10^9.\r\n" );
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document.write( "q=?\r\n" );
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document.write( "    Substitute the values into the basic formula\r\n" );
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document.write( "\"9.8%2A10%5E%28-4%29\" = \"%289.0%2A10%5E9%29+%2A%28q%5E2%2F+0.1%5E2%29\"\r\n" );
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document.write( "\"q%5E2\" = \"%28%289.8%2A10%5E%28-4%29%29%2A%280.1%5E2%29%29%2F+%289.0%2A10%5E9%29\"\r\n" );
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document.write( "\"q%5E2\" = \"%289.8%2F9.0%29%2A10%5E%28-15%29\"\r\n" );
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document.write( "\"q%5E2\" = \"1.0888+%2A+10%5E%28-15%29\" = \"10.888+%2A+10%5E%28-16%29\"\r\n" );
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document.write( "q = \"3.23%2A10%5E%28-8%29\"     <<<---===  ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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