Final answer:
As a particle moves from the outer to inner edge on a disc in a cyclotron, it speeds up due to conservation of angular momentum. Similarly, when light passes from air to a denser medium like water or glass, its speed and wavelength decrease, and the ray bends toward the normal.
Step-by-step explanation:
When a particle moves from the outer edge to the inner edge on a disc within a device like a cyclotron, it speeds up due to the conservation of angular momentum. In physics, as a particle moves closer to the axis of rotation, it must move faster if no external torque is applied. This is analogous to a figure skater pulling in their arms to spin faster.
In a cyclotron, as the particle moves in a spiral path from the outer edge to the inner edge, the frequency of the accelerating electric field is synchronized with the particle's motion to ensure continuous acceleration. Each time the particle completes a loop, the rate of voltage oscillation remains the same, but the particle travels faster and faster.
When considering the interaction of light and different media, if a ray of light travels from a less dense to a more dense medium, such as air into water or glass, the light ray will bend toward the normal line and the speed of the light decreases while the wavelength also decreases.