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.
Answer:
Strength
Explanation:
A huge number of systems use a process called Pseudo Random Number Generation (PRNG). In NIST SP 800-90, The PRNG has a set of parameters that define various variables within the algorithm. The PRNG variable strength is defined in NIST SP 800-90 as a number associated with the amount of work required to break a cryptographic algorithm or system.
The correct answer to this question is a certificate of deposit.
A certificate of deposit is an interest bearing account that pays a higher rate of interest than a savings account or interest bearing checking account because you are committing to leave it in the bank for a specified period of time. The CD could be for serveral months, or extend out to multiple years. Normally the interest rate will increase as the length of time increases.
