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.
3% of pedestrian fatalities were caused by impaired drivers
Wipe off the hard drive with a software eraser but it won't be quick and won't work on defective disks
Answer:
mystr = input("Enter a string ")
length = len(mystr)
while length<10:
mystr = input("Enter a string ")
length = len(mystr)
if(length>=10):
break
if len(mystr)%2==0:
print(mystr.lower())
else:
print(mystr.upper())
Explanation:
The variable mystr is used to save user's input which is received with the input function
A second variable length is used to save the length of the input string Using a while statement the user is continually prompted to enter a string while length is less than 10.
If length is greater or equal to 10. We check for even or odd using the modulo (%) operator.
We use lower() and upper() to change the case of the string
L is a decidable language because the Turing machine accepts it.
L is a recognizable language if TM M recognizes it.
<h3>How do you know if a language is decidable?</h3>
A language is said to be decidable only when there seems to exists a Turing machine that is said to accepts it,
Here, it tends to halts on all inputs, and then it answers "Yes" on words that is seen in the language and says "No" on words that are not found in the language. The same scenario applies to recognizable language.
So, L is a decidable language because the Turing machine accepts it.
L is a recognizable language if TM M recognizes it.
Learn more about programming language from
brainly.com/question/16936315
#SPJ1
