In [1]:

```
#given
D=1 #Distance of screen from the slit in m
w=6000 #Wavelength in Angstrom
w1=0.6 #Slit width in mm
#Calculations
x=((2*D*w*10**-10)/(w1*10**-3))*1000
#Output
print"Width of central band is ",x,"mm"
```

In [1]:

```
#given
d1=6000.0 #Diffraction grating have number of lines per cm
q=50 #Diffracted second order spectral line observed in degrees
n=2 #Second order
#Calculations
import math
w=(math.sin(q*3.14/180.0)/(d1*n))*10**8
#Output
print"Wavelength of radiation is ",round(w,1),"Angstrom"
```

In [5]:

```
#given
d1=6000 #Diffraction grating have number of lines per cm
w=6000 #Wavelength in Angstrom
#Calculations
n=(1/(d1*w*10**-8))
#Output
print"Maximum order of diffraction that can be observed is ",round(n,2)
```

In [7]:

```
#given
B=(3*3.14)/2 #First secondary maxima at B
#Calculations
import math
I=(math.sin(B)/B)**2
#Output
print"Ratio of intensity of central maxima to first secondary maxima is ",round(I,3)
```

In [8]:

```
#given
w=6400 #Wave length of light in Angstrom
w1=0.3 #Slit width in mm
d=110 #Distance of screen from the slit in cm
n=3 #order
#Calculations
x=((n*w*10**-10*(d/100.0))/(w1*10**-3))*1000
#Output
print"Distance between the centre of the central maximum and the third dark fringe is ",x,"mm"
```