In [1]:

```
import math #Example 11_1
#To find out how much heat is required to change the temperature
#With 400 Grams of water
c=1 #units in cal/g Centigrade
m=400 #Units in gm
t=5 #Units in centigrade
q=c*m*t #Units in Cal
print "The heat required for 400 gm of water is Q=",round(q)," Cal\n"
#With 400 grams of copper
c=0.093 #units in cal/g Centigrade
m=400 #Units in gm
t=-5 #Units in centigrade
q=c*m*t #Units in Cal
print "The heat required for 400 gm of copper is Q=",round(q)," Cal\n"
```

In [2]:

```
import math #Example 11_2
#To findout how much water is released
#When it crystallizes
m=50 #Units in gm
h=80 #Units in Cal/gm
q=m*h #Units in Cal
print "When it crystallizes heat required is Q=",round(q)," Cal\n"
#When it Condenses
m=50 #Units in gm
h=539 #Units in Cal/gm
q=m*h #Units in Cal
print "When it condenses heat required is Q=",round(q)," Cal\n"
#In textbook answer is printed wrong as Q=27000 cal but the correct answer is Q=26950 Cal
```

In [3]:

```
import math #Example 11_3
#To findout the amount of Ice that has to be added
m=200 #Units in gm
c=1 #Units in Cal/gm Centigrade
tf=60 #Units in Centigrade
to=98 #Units in Centigrade
change=m*c*(tf-to) #units in Cal
tf=60 #Units in centigrade
to=0 #Units in centigrade
Hf=80 #Units in Cal/gm
change1=Hf+c*(tf-to) #Units in Cal/gm
M=change/-(change1)
print "The amount of ice that has to be added is M=",round(M,1)," gm"
```

In [5]:

```
import math #Example 11_4
#To findout the specific heat capacity of the metal
m=400 #Units in gm
c=0.65 #Units in Cal/gm Centigrade
tf=23.1 #Units in Centigrade
to=18 #Units in Centigrade
oil=m*c*(tf-to) #units in cal
m1=80 #Units in gm
tf=23.1 #Units in Centigrade
to=100 #Units in Centigrade
cm=m1*(tf-to) #units in in terms of cm and gm Centigrade
cmm=oil/-cm #Units in Cal/gm Centigrade
print "The specific heat of metal is Cm=",round(cmm,3)," cal/gm C"
```

In [6]:

```
import math #Example 11_5
#To findout how long does the heater takes to heat
m=500 #Units in gm
c=0.033 #Units in Cal/gm Centigrade
tf=357 #Units in Centigrade
to=20.0 #Units in Centigrade
m1=30 #Units in gm
hv=65 #Units in cal/gm
Hg=((m*c*(tf-to))+(m1*hv))*4.1808135 #units in Joules
delivered=70 #Units in Joule/Sec
t=Hg/delivered #Units in sec
print "The time taken is t=",round(t)," sec"
#In textbook answer printed wrong as t=450 sec correct answer is t=448 sec
```

In [7]:

```
import math #Example 11_6
#To findout the rise in temperature
m=0.01 #Units in Kg
v=100 #Units in meters/sec
KE=(0.5*m*v**2)/4.1808135 #units in Cal
m=10 #units in gm
c=0.031 #units in cal/gm Centigrade
t=KE/(m*c)
print "the rise in temperature is DeltaT=",round(t,1)," C"
```

In [8]:

```
import math #Example 11_8
#To findout how much longer is at 35 degrees
alpha=10*10**-6 #Units in Centigrade
dist=20.0 #Unis in meters
t=50 #Units in centigrade
L=alpha*dist*t #Units in meters
print "The slab is longer by=",round(L,3)," meters"
```

In [9]:

```
import math #Example 11_9
#To findout how large a diameter when the sheet is heated
dist=2 #Units in cm
delta=19*10**-6 #Units in Centigrade**-1
t=200 #Units in centigrade
L=dist*delta*t #Units in cm
print "The new diameter of the hole is=",round(2+L,4)," cm"
```

In [10]:

```
import math #Example 11_10
#To findout the change in benzene volume
delta=1.24*10**-3 #Units in Centigrade**-1
t=10 #Units in Centigrade
v10=100.0 #Units in cm**3
v20=delta*t+v10 #Units in cm**3
V=v20*delta*t #Units in cm**3
v30=V+v20 #Units in cm**3
print "The change in benzene volume is V30=",round(v30,3)," cm**3"
#In textbook the answer is printed wrng as V3=0102.5 cm**3 the correct answer is V3=101.253 cm**3
```

In [11]:

```
import math #Example 11_11
#To findout how much ice melts each hour
s=30 #Units in cm
a=s*s*10**-4 #units in meter**2
k=0.032 #Units in W/K meter
t=25 #Units in K
l=0.040 #Units in meters
q_t=(6*k*((a*t)/l))/4.1808135 #Units in cal/sec
Q=3600*q_t #Units in cal
qq=80 #Units in cal/gm
melted=Q/qq #Units in gm
print "The ice melts by ",round(melted)," gm"
```

In [12]:

```
import math #Example 11_12
#To compare the energy emitted per unit area of our body to with the same emissivity
t1=37.0 #Units in Centigrade
t1=273+t1 #Units in K
t2=15 #Units in Centigrade
t2=273+t2 #Units in K
tb_tc=(t1/t2)**4 #Units in terms of (Tb/Tc)**4
tb_tc=tb_tc*100 #In terms of percentage
print "The radiation defers by ",round(tb_tc-100)," percent"
#In textbook answer is printed wrong as 40% the correct answer is 34%
```

In [13]:

```
import math #Example 11_13
#To findout how much heat is lost through it
a=15 #Unis in meter**2
t=30.0 #Units in K
R=2.2 #Units in Meter**2 K/W
q_t=(a*t)/R #Units in W
T=3600.0 #Units in sec
Q=q_t*T #Units in J
print "The amount of heat lost is Q=",round(Q,1)," J"
```