In [4]:

```
# Variable Declaration
n1 = 1.50 # Refractive Index of Substance 1
n2 = 1.46 # Refractive Index of Substance 2
# Calculation
import math # Math Library
THEETA_c = math.asin(n2/n1) # Critical angle of incidence (degrees)
# Result
print "The critical angle of incidence between two given substances is THEETA_c =",round(THEETA_c*180/math.pi,1),"degrees."
```

In [7]:

```
# Variable Declaration
tr = 2.00*pow(10,-9) # Rise Time (s)
Cd = 3.00*pow(10,-12) # Capacitance (F)
Cdh = 2.00*pow(10,-12) # Assumed Capacitance (F)
# Calculation
import math # Math Library
BW = 0.35/tr # Bandwidth (Hz)
Rl = 1/(2*math.pi*BW*Cdh) # Resistance (Ohms)
# Result
print "BW =",round(BW/pow(10,6)),"MHz"
print "Rl =",round(Rl),"Ohms"
print "In practice, a value approximately 25 percent of this calculated value will be used."
```

In [12]:

```
# Variable Declaration
Mu_A = 40.00 # Diode Current (uW)
Mu_W = 80.00 # Incident Light (uW)
# Calculation
import math # Math Library
R = Mu_A/Mu_W # Responsivity (A/W)
# Result
print "The Responsivity of the light detector is R =",round(R,1),"A/W."
```