Answer:
t = 56.6 min
Explanation:
Fick's second law is used to calculate time required for diffusion
where
= 1.15%
= 0.18%
= 0.35%
x = 0.40 mm = 0.0004 n
therefore we ahave
![\frac{1.15-0.35}{1.15- 0.18} = erf[\frac{4\times 10^{-4}}{2\sqrt{1.28\times 10^{-11} t}}]](https://tex.z-dn.net/?f=%5Cfrac%7B1.15-0.35%7D%7B1.15-%200.18%7D%20%3D%20%20erf%5B%5Cfrac%7B4%5Ctimes%2010%5E%7B-4%7D%7D%7B2%5Csqrt%7B1.28%5Ctimes%2010%5E%7B-11%7D%20t%7D%7D%5D)
![0.8247 = erf [\frac{55.90}{\sqrt{t}}] = erf z](https://tex.z-dn.net/?f=0.8247%20%3D%20erf%20%5B%5Cfrac%7B55.90%7D%7B%5Csqrt%7Bt%7D%7D%5D%20%3D%20%20erf%20z)
from error function table we hvae following result
for erf z z
0.8209 0.95
0.8247 x
0.8427 1
therefore
x = 0.959
thus
t = 56.6 min
Answer:
A safe enveroment.
Explanation:
Sirens usally mean fire or someone died.
Answer:
32000 bits/seconds
Explanation:
Given that :
there are 16 signal combinations (states) = 2⁴
bits n = 4
and a baud rate (number of signals/second) = 8000/second
Therefore; the number of bits per seconds can be calculated as follows:
Number of bits per seconds = bits n × number of signal per seconds
Number of bits per seconds = 4 × 8000/second
Number of bits per seconds = 32000 bits/seconds
Answer:
A
Explanation:
because Farmers in hilly areas grow crops on terraces built on the hillsides.
