Final answer:
Ground clutter on a radar screen is typically seen as a donut shape due to the interaction of the radar beam with objects on the ground. A lunch box released on a merry-go-round will follow a curved path (path C) as viewed from the Earth's frame of reference due to the Coriolis effect and inertial forces.
Step-by-step explanation:
Ground clutter typically refers to the unwanted echoes on radar screens that can occur when the radar beam interacts with surfaces such as the ground, buildings, or trees. This can cause a pattern that is often seen as a circle or more commonly as a donut shape around the radar site. The center of the donut is relatively clear because the radar is typically angled slightly upward so it doesn't directly hit the ground or objects very close to the radar site. However, as the beam travels outward and comes back down to earth, it can reflect off taller objects or uneven terrain, creating echoes that show up on the radar screen as a ring, hence the donut shape.
Regarding the question about the child's lunch box released on a merry-go-round, the path it follows as viewed from the Earth's frame of reference will not be a straight line due to the Coriolis effect. Instead, the lunch box would follow what seems to be a curved path because the merry-go-round is rotating underneath it. This curve is the result of the inertial forces acting on the lunch box as it tries to maintain its linear velocity in the rotating reference frame of the merry-go-round. Thus, the path will resemble path C, which is a curved trajectory.