document.write( "Question 973255: The density of platinum is 21.5g/cm^3. If the ring shown in the figure below is crafted out of platinum, how much will it weigh?\r
\n" ); document.write( "\n" ); document.write( "h = 0.5 cm
\n" ); document.write( "r = 2 cm
\n" ); document.write( "0.15 cm
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Algebra.Com's Answer #595550 by macston(5194)\"\" \"About 
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\n" ); document.write( "Assuming 0.15cm is the thickness, the volume will be
\n" ); document.write( "volume of the disk with outside radius (r) and thickness (h)
\n" ); document.write( "minus the the inner (empty) disk with radius (r-0.15cm) and
\n" ); document.write( "thickness h:
\n" ); document.write( "\"%28pi%29r%5E2h-%28pi%29%28r-0.15cm%29%5E2h\"=volume of metal in ring
\n" ); document.write( "\"%28pi%29%282cm%29%5E2%280.5cm%29-%28pi%29%282cm-0.15cm%29%5E2%280.5cm%29=volume\"
\n" ); document.write( "\"%28pi%29%282cm%5E3%29-%28pi%29%281.71cm%5E3%29=volume\"
\n" ); document.write( "\"%28pi%29%282cm%5E3-1.71cm%5E3%29=volume\"
\n" ); document.write( "\"%28pi%29%280.29cm%5E3%29=volume\"
\n" ); document.write( "\"0.911cm%5E3=volume\"
\n" ); document.write( ".
\n" ); document.write( "Mass=density x volume:
\n" ); document.write( "\"mass=%2821.5g%2Fcm%5E3%29%280.911cm%5E3%29\"
\n" ); document.write( "\"mass=19.587g\"\r
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