document.write( "Question 1202261: construction crew wants to hoist a heavy beam so that it is standing up straight. They
\n" ); document.write( "tie a rope to the beam, secure the base, and pull the rope through a pulley to raise one end
\n" ); document.write( "A of the beam from the ground. When the beam makes an angle of 40o with the ground, the
\n" ); document.write( "top of the beam is 8 ft above the ground.
\n" ); document.write( "The construction site has some telephone wires crossing it.. The workers are concerned
\n" ); document.write( "that the beam may hit the wires. When the beam makes an angle of 60o with the ground,
\n" ); document.write( "the wires are 2 ft above the top of the beam. Will the beam clear the wires on its way to
\n" ); document.write( "standing up straight? Explain your answer\r
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Algebra.Com's Answer #853492 by ikleyn(53595) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "A construction crew wants to hoist a heavy beam so that it is standing up straight. They
\n" ); document.write( "tie a rope to the beam, secure the base, and pull the rope through a pulley to raise one end
\n" ); document.write( "A of the beam from the ground. When the beam makes an angle of 40o with the ground, the
\n" ); document.write( "top of the beam is 8 ft above the ground.
\n" ); document.write( "The construction site has some telephone wires crossing it.. The workers are concerned
\n" ); document.write( "that the beam may hit the wires. When the beam makes an angle of 60o with the ground,
\n" ); document.write( "the wires are 2 ft above the top of the beam. Will the beam clear the wires on its way to
\n" ); document.write( "standing up straight? Explain your answer
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\n" ); document.write( "\n" ); document.write( "        The analysis in the post by @mananth is incorrect\r
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\n" ); document.write( "\n" ); document.write( "        I came to bring a correct solution.\r
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document.write( "We find the length of the beam L from the condition\r\n" );
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document.write( "    sin(40°) = ,  L =  =  = 12.45 ft  (approximately).\r\n" );
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document.write( "The height of the wires is  L*sin(60°) + 2 =  + 2 = 10.78 + 2 = 12.78 ft.\r\n" );
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document.write( "The length of the beam, 12.45 ft, is less than the height of the wires, 12.78 ft,\r\n" );
document.write( "which means that the beam will pass below the wires.             <<<---===  ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved correctly.\r
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