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The critical fields at 6k at 8k for an alloy are 7.616 & 4.284 Wb/m² resp. Determine the transition temperature and critical field at 0 k temperature? ​

User Parulb
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Answer:

The transition temperature is 0.920 K and the critical field at 0 K is 8.956 Wb/m².

Step-by-step explanation:

To determine the transition temperature and critical field at 0 K, we need to use the following formula:

Bc(T) = Bc(0)[1-(T/Tc)^2]

where:

Bc(T) = critical magnetic field at temperature T

Bc(0) = critical magnetic field at 0 K

T = temperature

Tc = transition temperature

We have the critical fields at 6 K and 8 K:

Bc(6 K) = 7.616 Wb/m²

Bc(8 K) = 4.284 Wb/m²

We can use these values to find the transition temperature:

7.616 = Bc(0)[1-(6/Tc)^2]

4.284 = Bc(0)[1-(8/Tc)^2]

Dividing the two equations, we get:

7.616/4.284 = [1-(6/Tc)^2]/[1-(8/Tc)^2]

Simplifying the right-hand side:

7.616/4.284 = [(8/Tc)^2 - 1]/[(6/Tc)^2 - 1]

Let x = (8/Tc)^2

Then (6/Tc)^2 = x/64

Substituting into the equation above:

7.616/4.284 = (x - 1)/(x/64 - 1)

Simplifying:

7.616/4.284 = 64(x - 1)/(x - 64)

Multiplying both sides by (x - 64):

7.616/4.284 * (x - 64) = 64(x - 1)

Simplifying:

(x - 64)/(x - 1) = 7.616/4.284 * 1/64

Multiplying both sides by (x - 1):

x - 64 = 7.616/4.284 * 1/64 * (x - 1)

Simplifying:

x = 74.14

Substituting back into (8/Tc)^2 = x:

(8/Tc)^2 = 74.14

8/Tc = ±8.607

Tc = 0.920 K or 0.103 K

Since the transition temperature should be higher than the critical field at 0 K, we choose Tc = 0.920 K.

Now we can use either of the equations for Bc(T) to find Bc(0):

7.616 = Bc(0)[1-(6/0.920)^2]

Bc(0) = 8.956 Wb/m²

Therefore, the transition temperature is 0.920 K and the critical field at 0 K is 8.956 Wb/m².

User Feloneous Cat
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