Answer:
Diffusion time is 7.42 h
Solution:
As per the question:
Temperature, T = 
Surface concentration of arsenic, 
Surface concentration below Silicon surface, 
D = 
x = 
Initial concentration at t = 0, 
Now, by using Flick's second eqn:
Thus by putting appropriate values:
(1)
Now,
Now, from error function values tabulation:
For z = 2.0, erf(z) = 0.998
For z = 2.2, erf(z) = 0.995
Now,
With the help of linear interpolation method:
z = 2.12
Now, using eqn (1) and above value:
= 26700 s
t = 
Solid because the particles vibrate in place
Answer:
The tension is 75.22 Newtons
Explanation:
The velocity of a wave on a rope is:
(1)
With T the tension, L the length of the string and M its mass.
Another more general expression for the velocity of a wave is the product of the wavelength (λ) and the frequency (f) of the wave:
(2)
We can equate expression (1) and (2):
=
Solving for T
(3)
For this expression we already know M, f, and L. And indirectly we already know λ too. On a string fixed at its extremes we have standing waves ant the equation of the wavelength in function the number of the harmonic 
is:
It's is important to note that in our case L the length of the string is different from l the distance between the pin and fret to produce a Concert A, so for the first harmonic:
We can now find T on (3) using all the values we have:
Travis Scott!3&;8284$28&:!;&29395
Answer:
n = 1.7*10²² electrons.
Explanation:
- As the current, by definition, is the rate of change of charge, assuming that the current was flowing at a steady rate of .151 A during the 5 hours, we can find the total charge that passed perpendicular to the cross-section of the circuit, as follows:
⇒ Δq = I * Δt = 0.151 A * 18000 s = 2718 C
- As this charge is carried by electrons, we can express this value as the product of the elementary charge e (charge of a single electron) times the number of electrons flowing during that time, as follows:
Δq = n*e
