1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
{
"metadata": {
"name": "",
"signature": "sha256:c4f4158f2a13ac09e07abe135472c68abbdd09915f4866e5eedc3ddf9b9f42f5"
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"9: Superconductivity"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 9.1, Page number 9.3"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#importing modules\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable declaration\n",
"Tc = 3.7 #critical temperature(K)\n",
"Hc_0 = 0.0306 #critical field(T)\n",
"T = 2 #temperature(K)\n",
"\n",
"#Calculation\n",
"Hc_2 = Hc_0*(1-(T/Tc)**2) #critical field(T)\n",
"Hc_2 = math.ceil(Hc_2*10**5)/10**5 #rounding off to 5 decimals\n",
"\n",
"#Result\n",
"print \"critical field at 2K is\",Hc_2,\"T\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"critical field at 2K is 0.02166 T\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 9.2, Page number 9.5"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#importing modules\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable declaration\n",
"T = 4.2 #temperature(K)\n",
"d = 1 #diameter(mm)\n",
"Tc = 7.18 #critical temperature(K)\n",
"H0 = 6.5*10**4 #critical field(A/m)\n",
"\n",
"#Calculation\n",
"d = d*10**-3 #diameter(m)\n",
"Hc = H0*(1-((T/Tc)**2)) #critical field at 2K(A/m)\n",
"ic = math.pi*d*round(Hc); #critical current(A)\n",
"ic = math.ceil(ic*10**2)/10**2; #rounding off to 2 decimals\n",
"\n",
"#Result\n",
"print \"critical current for lead is\",ic,\"A\"\n",
"print \"answer given in the book differs due to rounding off errors\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"critical current for lead is 134.34 A\n",
"answer given in the book is wrong\n"
]
}
],
"prompt_number": 10
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 9.3, Page number 9.13"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#importing modules\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable declaration\n",
"lamda_T = 750 #penetration depth of mercury(Armstrong)\n",
"T = 3.5 #temperature(K)\n",
"Tc = 4.12 #critical temperarure(K)\n",
"\n",
"#Calculation\n",
"lamda_0 = lamda_T*((1-(T/Tc)**4))**(1/2) #penetration depth(Armstrong)\n",
"\n",
"#Result\n",
"print \"penetration depth at 0K is\",int(lamda_0),\"armstrong\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"penetration depth at 0K is 519 armstrong\n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example number 9.4, Page number 9.13"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#importing modules\n",
"import math\n",
"from __future__ import division\n",
"\n",
"#Variable declaration\n",
"T1 = 3 #temperature(K)\n",
"T2 = 7.1 #temperature(K)\n",
"lamda_T1 = 396 #penetration depth(armstrong)\n",
"lamda_T2 = 1730 #penetration depth(armstrong)\n",
"\n",
"#Calculation\n",
"A = (((lamda_T2/lamda_T1)**2)*T2**4) - T1**4\n",
"B = ((lamda_T2/lamda_T1)**2)-1\n",
"Tc = (A/B)**(1/4) #critical temperature(K)\n",
"Tc = math.ceil(Tc*10**4)/10**4; #rounding off to 4 decimals\n",
"\n",
"#Result\n",
"print \"critical temperature for lead is\",Tc,\"K\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"critical temperature for lead is 7.1932 K\n"
]
}
],
"prompt_number": 4
}
],
"metadata": {}
}
]
}
|