Correct option is B
Concept:
Translational Motion: The center of the ring moves forward in a straight line, maintaining a constant speed.
This is because the ring is moving along a flat surface.
Rotational Motion: At the same time, the ring is rotating around its center. Each point on the ring traces a
circular path relative to the center of the ring.
Solution:
When a ring rolls without slipping, the motion of any point on the ring can be described by a combination
of rotational and translational motion. The key observation is that the point that is at the top of the ring will trace
a circular arc relative to the center of the ring, while the entire ring itself is moving forward due to the rolling.
As the ring rolls, the topmost point (the marked one) moves forward, downward, and around the circumference of the ring
while the entire ring also moves forward along the track.
After some rolling, the marked point will come down as the ring rotates and eventually reach a lower position on
the ring compared to its starting point.
Position B shows the correct behavior, where the marked point has moved forward and downward as expected for a rolling motion.
Therefore, Option b is the correct answer.
