The period of electron revolution in a uniform magnetic field with an induction of 5.6TL is 6 ns.
The period of electron revolution in a uniform magnetic field with an induction of 5.6TL is 6 ns. The radius of the circle described by the electron is 1 cm. Determine: the speed of the electron: the force acting on the electron from the side of the magnetic field.
T = 6 ns = 6 * 10-9 s.
B = 5.6 T.
q = 1.6 * 10-19 Cl.
∠α = 90 °.
R = 1 cm = 0.01 m.
m = 9.1 * 10-31 kg.
V -?
Fl -?
In a magnetic field, the electron is acted upon by the Lorentz force Fl: Fl = q * V * B * sinα.
m * a = q * V * B * sinα – 2 Newton’s law.
The centripetal acceleration a is expressed by the formula: a = V2 / R.
m * V2 / R = q * V * B * sinα.
The electron velocity V is expressed by the formula: V = q * B * sinα * R / m.
V = 1.6 * 10-19 C * 5.6 T * sin90 ° * 0.01 m / 9.1 * 10-31 kg = 0.008 * 1012 m / s.
Fl = 1.6 * 10-19 C * 5.6 T * sin90 ° * 0.008 * 1012 m / s = 0.07 * 10-7 N.
Answer: the speed of the electron is V = 0.008 * 1012 m / s, the Lorentz force acts on the electron Fl = 0.07 * 10-7 N.