An electron is accelerated from rest through 2300 V and then enters a region of uniform magnetic field with magnitude 1.25 T. What is the magnitude of the maximum magnetic force acting on the electron?

Explanation:

Given that,

The electron accelerated from rest through 2300V, then the Potential difference is 2300V

V = 2300V.

Magnetic field of 1.25T

B= 1.25T

Mass of electron

m = 9.11 ×10^-31kg

Charge of an electron

q = 1.602 ×10^-19C

Maximum magnetic force?

Maximum magnetic force can be determined using

Fmax = qvB

We don't know the velocity(v) but it can be determine using

Work done by potential = Kinectic energy

qV = ½mv²

Rearranging

v = √(2qV/m)

v = √(2×1.602×10^-19 × 2300/9.11×10^-31)

v = 2.84 × 10^7 m/s

Then,

Maximum Magnetic force

Fmax = qvB

Fmax=1.602×10^-19×2.84×10^7×1.25

Fmax = 5.7 × 10^-12 N

The magnitude of the maximum magnetic force is 5.7 × 10^-12 N