This diagram shows the path of an electron as it travels in air. The electron rotates clockwise around a uniform magnetic field into the plane of the paper, but the radius of the orbit decreases in size.

a i. Explain the origin of the force that causes the electron to spiral in this manner.
ii. Explain why the radius of the circle gradually decreases.
b. At one point in the path, the speed of the electron is 1.0 × 10⁷ m s⁻¹ and the magnetic flux density is 0.25 T. Calculate:
i. The force on an electron at this point due to the magnetic field
ii. The radius of the arc of the circular path at this point.

Transcribed Image Text:

Figure 25.16