Answer:
a) D = 4.88 * 10^(-14) m^2 / s
b) <em>t </em>= 1.1 hr
Solution:
a) Magnesium in Aluminum diffusion:
D = Do * exp(-Qd / RT)
= (1.2 * 10^(-4) m^2 / s) * exp ( - 130,000 / 8.31 * 723.15)
= 4.88 * 10^(-14) m^2 / s
D = 4.88 * 10^(-14) m^2 / s
b) The composition remains same at say the distance Xo:
(Cx - Co) / (Cs - Co) = Constant
Xo^2 / D_{550} * <em>t </em>= Xo^2 / D_{450} * 15
D_{550} * <em>t </em>= D_{450} * 15
(1.2 * 10^(-4) m^2 / s) * exp ( - 130,000 / 8.31 * 723.15) * <em>t</em>
(4.88 * 10^(-14) m^2 / s) * 15
by, solving for <em>t </em>we get:
<em>t </em>= 1.1 hr
So, the time required is 1.1 hr.
A bar graph is a great graphical representation of disributiation of data
Answer : computer
Explanation:
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Answer:
The history of agriculture in the United States covers the period from the first English settlers to the present day. In Colonial America, agriculture was the primary livelihood for 90% of the population, and most towns were shipping points for the export of agricultural products. Most farms were geared toward subsistence production for family use. The rapid growth of population and the expansion of the frontier opened up large numbers of new farms, and clearing the land was a major preoccupation of farmers. After 1800, cotton became the chief crop in southern plantations, and the chief American export. After 1840, industrialization and urbanization opened up lucrative domestic markets. The number of farms grew from 1.4 million in 1850, to 4.0 million in 1880, and 6.4 million in 1910; then started to fall, dropping to 5.6 million in 1950 and 2.2 million in 2008
Explanation:
Answer:
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Most alternative presses aren't reliable and are effectively tabloids in nature, but their content differs.
