Question

multiple choice question
at a great enough distance from a source, a small part of a ———— wave can be considered a ———— wave front.
spherical; linear
plane; spherical
sound; light
light; sound

Explanation:

• A spherical wave has wavefronts that are spheres centered at the source. As the distance from the source becomes very large, a small part of the spherical wavefront can be approximated as a linear (or planar - in a 2D sense, linear is a simple way to describe it compared to the spherical curvature) wavefront.
• A plane wave has flat wavefronts from the start, so it cannot be a small part of a spherical wave. Sound and light are types of waves, not wavefront shapes in this context.

Answer:

spherical; linear