Can a material have negative permittivity?

Carbon is allowed to diffuse through a steel plate 9.7-mm thick. The concentrations of carbon at the two faces are 0.664 and 0.3

cupoosta [38]

Answer:

844°C

Explanation:

The problem can be easily solve by using Fick's law and the Diffusivity or diffusion coefficient.

We know that Fick's law is given by,

$J = - D \frac{\Delta c}{\Delta x}$

Where $\frac{\Delta c}{\Delta x}$ is the concentration of gradient

D is the diffusivity coefficient

and J is the flux of atoms.

In the other hand we have, that

$D= D_0 e^{\frac{E_d}{RT}}$

Where $D_0$ is the proportionality constant,

R is the gas constant, T the temperature and $E_d$ is the activation energy.

Replacing the value of diffusivity coefficient in Fick's law we have,

$J = -D_0 ^{\frac{E_d}{RT}}\frac{\Delta c}{\Delta x}$

Rearrange the equation to get the value of temperature,

$T=\frac{Ed}{Rln(\frac{J\Delta x}{D_0 \Delta c})}$

We have all the values in our equation.

$\Delta c = 0.664-0.339 = 0.325 C. cm^{-1}$

$\Delta x = 9.7*10^{-3}m$

$E_d = 82000J$

$D_0 = 6.5*10^{-7}m^2/s$

$J = 3.2*10^{-9}m^2/s$

$R= 8.31Jmol^{-1}K$

Substituting,

$T=\frac{Ed}{Rln(\frac{J\Delta x}{D_0 \Delta c})}$

$T=-\frac{-82000}{(8.31)ln(\frac{3.2*10^{-9}(9.7*10^{-3})}{6.5*10^{-7} (0.325)})}$

$T=1118.07K=844\°C$

4 0

3 years ago

What is the momentum of a 200 kg football player running west at a speed of 8m/s

lutik1710 [3]

Answer:

<h3>The answer is 1600 kgm/s</h3>

Explanation:

The momentum of an object can be found by using the formula

<h3>momentum = mass × velocity</h3>

From the question

mass = 200 kg

velocity / speed = 8m/s

We have

momentum = 200 × 8

We have the final answer as

Hope this helps you

7 0

3 years ago

If the temperature of a piece of steel decreases, what happens to its density? (1 point)

zlopas [31]

As temperature decreases, the steel will contract (volume decreases) thereby, an increase in Density.

3 0

3 years ago

Read 2 more answers

You stand new the earth's equator. A positively charged particle that starts moving parallel to the surface of the earth in a st

Talja [164]

Answer:

c. from south to north

Explanation:

since we know that:

F = qv×B

where F is the force and in this case is pointed upward

where v is the velocity due east

the field must be due north by the right hand rule

Therefore, near the equator the magnetic field lines of the earth are directed north from south

3 0

3 years ago

Which orgen in the urinary system regulates the water content and remove the toxic waste products from the blood?

topjm [15]

Answer:

The Kidneys

Explanation:

The Kidneys remove the toxic stuff that you dont need anymore. Therefore the kidneys rather than the everything else removes blood and toxic waste.

4 0

3 years ago