Answer:
0.23348 A
Explanation:
B = Magnetic field
v = Velocity of electron = [tex]1.38\times 10^7\ m/s[/tex]
q = Charge of electron = [tex]1.6\times 10^{-19}\ C[/tex]
[tex]\mu_0[/tex] = Vacuum permeability = [tex]4\pi \times 10^{-7}\ H/m[/tex]
r = Radius of circle = 0.026 m
N = Number of turns = 103 turns/cm = [tex]103\times 100\ turns/m[/tex]
I = Current
The magnetic and centripetal force will be balanced
[tex]Bqv=m\frac{v^2}{r}\\\Rightarrow B=\frac{mv}{qr}[/tex]
The magnetic field in solenoid is given by
[tex]B=N\mu_0 I\\\Rightarrow I=\frac{B}{N\mu_0}[/tex]
From the first equation
[tex]I=\frac{\frac{mv}{qr}}{N\mu_0}\\\Rightarrow I=\frac{mv}{N\mu_0qr}\\\Rightarrow I=\frac{9.11\times 10^{-31}\times 1.38\times 10^7}{103\times 100\times 4\pi \times 10^{-7}\times 1.6\times 10^{-19}\times 0.026}\\\Rightarrow I=0.23348\ A[/tex]
The current in the solenoid is 0.23348 A