Final answer:
The claim that a gnomonic light source is located at the center of a globe is false. The term 'gnomonic' refers to map projections or sundials and is not associated with the position of a light source in relation to mirrors or lenses.
Step-by-step explanation:
The statement that a gnomonic light source is located at the center of a globe is False. The term 'gnomonic' typically refers to a type of map projection or sundial, rather than a light source. In the context of light and optics, light sources are described in relation to their position to optical components such as mirrors and lenses.
When discussing light sources in the context of mirrors, the focus is typically on the relationship between the light source and the focal point or center of curvature of the mirrors.
For example, it is said that the bulb is at the focal point of the small mirror and at the center of curvature of the large mirror, or vice versa depending on the specific setup. This is a different scenario than declaring a light source as "gnomonic." Moreover, the description of Earth's shadow as a cone due to the Sun's finite size is unrelated to the idea of a gnomonic light source.