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Page: 2150 Sunday, May 19, 2013 |
The answer is calculated by multiplying the volume of the ball
by the density of the material.
Weight = Volume * Density
Volume = (4 *
* R * R * R)/ 3, or Volume = ( 4 * Pi
* Radius ^ 3 ) / 3
, Pi, a universal constant = 3.1416
4
= 12.566
R=Radius
R=Diameter / 2 = 2 / 2 = 1
R^3 = R * R * R = 1
12.566 x 1 = 12.566
12.566 / 3 = 4.1887 cubic inches (is the volume of a 2 inch ball)
4.1887 times the density of lead, which is 0.409 pounds per cubic inch, gives a weight of 1.713 pounds.
The radius of 1.5 inches cubed equals 3.375, times 12.566 ( 4
x
) equals
42.410, divided by three, equals 14.137 cubic inches, times 0.409
( the density of lead ) gives 5.782 pounds.
Weight = Volume * Density
Weight = [(4 *
* R * R * R)/ 3 ] * 0.409
Weight = [ ( 4 * 3.1416 * (3/2) * (3/2) * (3/2) /3 ] * 0.409
Weight = 5.782 pounds
Notice that only one inch increase in diameter caused a 4
pound increase in weight. This three inch diameter ball is more
than triple the weight of the two inch diameter ball.
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**See also: A density measurement conversion tool that is available at
http://www.easyunitconverter.com/density-unit-conversion/density-unit-converter.aspx , for density unit conversions of various materials such as brass, copper, steel, and aluminum.
http://www.convertauto.com from Lilly Hammond at NCSU.