The refracted beam angle is proportional to which of the following?

The refracted beam angle is directly related to Snell's law, which describes how waves, including sound waves, change direction when they pass between different media. According to Snell's law, the sine of the angle of incidence divided by the sine of the angle of refraction is equal to the ratio of the velocities (or sound speeds) of the two materials. Therefore, the refracted beam angle changes based on the incident angle and the relative sound speeds of the materials involved.

In this context, the factors of incident angle and relative sound speed are crucial. The incident angle refers to the angle at which the wave strikes the interface between two different materials, and the relative sound speed determines how rapidly sound travels in each medium, impacting how much the wave is refracted. Thus, understanding Snell's law and its relationship to these aspects is essential for predicting the behavior of the refracted beam.

The other options mentioned aspects that either do not apply to the refracted beam angle or focus on parameters that are not directly relevant to the angle change per Snell’s law.