Chapter 19 : Magnetism

Example 19.1 Page No: 631

In [2]:
q=1.6*10**-19#in columb
v=1*10**5#in m/s
B=55*10**-6#in T
F=q*v*B* 0.8660
print "The force = %0.2e Newton"%F

The force = 7.62e-19 Newton

Example 19.2 Page No: 632

In [4]:
q=1.6*10**-19#in columb
v=8*10**6#in m/s
B=2.5#in T
F=q*v*B* 0.8660
print "The force = %0.2e Newton"%F
m=1.67*10**-27
a=F/m
print "Acceleration = %0.2e m/s**2"%a

The force = 2.77e-12 Newton
Acceleration = 1.66e+15 m/s**2

Example 19.3 Page No: 635

In [5]:
l=36#in m
I=22#in A
B=0.50*10**-4#in T
F=B*I*l
print "The maximaum force = %0.2e Newton"%F

The maximaum force = 3.96e-02 Newton

Example 19.4 Page No: 637

In [7]:
from math import pi
A=pi*(0.5)*0.5#in m
I=2#in A
B=0.50#in T
T=B*I*A*0.5
print "The Torque = %0.2f N-m"%T

The Torque = 0.39 N-m

Example 19.5 Page No: 640

In [8]:
q=1.6*10**-19
B=.35
r=14*10**-2#in m
m=1.67*10**-27#kg
v=(q*B*r)/m
print "Velocity = %0.2e m/s"%v

Velocity = 4.69e+06 m/s

Example 19.6 Page No: 641

In [9]:
q=1.6*10**-19
B=.10#in T
v=1*10**6#in m/s
r=14*10**-2#in m
m1=1.67*10**-27#in kg
m2=3.34*10**-27#in kg
r1=(m1*v)/(q*B)
r2=(m2*v)/(q*B)
x=(2*r2)-(2*r1)
print "Radius of lighter istope = %0.2f m"%r1
print "Radius of heavier istope = %0.2f m"%r2
print "Distance of seperation = %0.2f m"%x

Radius of lighter istope = 0.10 m
Radius of heavier istope = 0.21 m
Distance of seperation = 0.21 m

Example 19.7 Page No: 644

In [12]:
from math import pi
Uo=(4*pi*10**-7)
I=5#in A
r=4*10**-3
B=(Uo*I)/(2*pi*r)
print "Magnetic field = %0.1e T"%B
q=1.6*10**-19
v=1.5*10**3#in m/s
F=q*v*B
print "Force = %0.e Newton"%F

Magnetic field = 2.5e-04 T
Force = 6e-20 Newton

Example 19.8 Page No: 646

In [14]:
from math import pi, sqrt
mo=4*pi*10**-7#Tm/A
d=0.1#in m
x=1*10**-4#F/l
I=sqrt((x*2*pi*d)/mo)
print "Current = %0.2f A"%I

Current = 7.07 A

Example 19.9 Page No: 649

In [15]:
from math import pi
N=100#turns
l=.1#in m
n=N/l#in turns/m
mo=4*pi*10**-7#Tm/A
I=.5#in A
B=n*I*mo
q=1.6*10**-19#in c
v=375#in m/s
F=q*v*(B/2)

print "Magnetic field = %0.2e T"%B
print "Force = %0.2e N"%F

Magnetic field = 6.28e-04 T
Force = 1.88e-20 N