import math
#initialisation of variables
r=3.0
Os=25.0
area=0.25
#Calculations
Ea=Os/(4.0*3.14*(r)**2)
Tf=Ea*area
#Results
print(" total flux is %3.3fW " %Tf)
import math
#initialisation of variables
Vcc=9.0
Vf=1.6
Vb=7.0
hFE=100.0
Vce=0.2
Ic=10.0*10**-3
Vbe=0.7
#Calculations
R2=(Vcc-Vf-Vce)/Ic
R2=680#use standard value
Ic=(Vcc-Vf-Vce)/R2
Ib=Ic/hFE
Rb=(Vb-Vbe)/Ib
#Results
print("The value of Rb is %d kohm" %(Rb/1000))
import math
#initialisation of variables
Vcc=5.0
N=(3*7.0)+(1.0*2)
#Calculations
It=N*10.0*10**-3
P=It*Vcc
#Results
print("The value of power is %.2f W" %P)
import math
#initialisation of variables
Rc=1.0*10**3
I=10.0*10**-3
E=30.0
#Calculations
R1=E/I -Rc
R1=1.8*10**3#use standard value
print(" when dark Rc=100Kohm")
Rc=100*10**3
I=E/(R1+Rc)
#Results
print("The value of I is %.2f mA" %(I*10**3))
import math
#initialisation of variables
Vee=6.0
Vbe=0.7
Ib=200.0*10**-6
Vb=0.7
Vcc=6.0
#Calculations
print("when cell is dark Rc=100Kohm")
Rc=100.0*10**3
Vrc=Vee+Vbe
Irc=Vrc/Rc
Ir1=Irc+Ib
Vr1=Vcc-Vb
R1=Vr1/Ir1
R1=18.0*10**3#use standard value
print(" when Q1 is off")
Vr1=6.0
Vrc=6.0
Ir1=Vr1/R1
Rc=Vrc/Ir1
#Results
print("The value of Rc is %d kohm" %(Rc/1000))