The drawing shows a steel ball rolling along a flat surface at constant velocity from point A to point B. A magnet exerts an attractive force on the ball only for the short time that passes as the ball rolls past point B. Which one of the following trajectories does the ball follow beyond point B and why?
The ball is slightly deflected toward the magnet, and it follows path 2.
The magnet has no affect on the steel ball, so it follows path 3.
The ball is slightly deflected away from the magnet, and it follows path 4.
The ball follows the nearly circular path, 5, because a repulsive force continues to act on it.
The ball follows the nearly circular path, 1, because an attractive force continues to act on it.
To determine the trajectory that the steel ball follows beyond point B, we need to understand the forces acting on the ball.
Initially, as the ball rolls along the flat surface from point A to point B at a constant velocity, there are no significant forces acting on it. However, once the ball passes point B, a magnet exerts an attractive force on the ball for a short time.
Based on this information, we can conclude that the ball will experience a force due to the magnet once it goes past point B. Now let's analyze the possible trajectories:
1. Path 1: The ball follows the nearly circular path. This option suggests that the ball continues to experience an attractive force from the magnet, resulting in a circular trajectory. However, the question states that the magnet exerts an attractive force "only for the short time that passes as the ball rolls past point B." Therefore, this option is incorrect.
2. Path 2: The ball is slightly deflected toward the magnet. This option suggests that the ball is attracted to the magnet and deviates from its initial path. This is a plausible scenario since the magnet exerts an attractive force on the ball. Therefore, this option is a possible trajectory for the ball beyond point B.
3. Path 3: The magnet has no effect on the steel ball. This option suggests that the magnet does not exert any force on the ball, which contradicts the given information. It is explicitly stated that the magnet exerts an attractive force on the ball. Therefore, this option is incorrect.
4. Path 4: The ball is slightly deflected away from the magnet. This option suggests that the ball is repelled by the magnet, which contradicts the given information that the magnet exerts an attractive force. Therefore, this option is incorrect.
5. Path 5: The ball follows the nearly circular path because a repulsive force continues to act on it. This option suggests that the ball is repelled by the magnet and follows a circular trajectory due to the repulsive force. However, the question clearly states that the magnet exerts an attractive force on the ball, not a repulsive force. Therefore, this option is incorrect.
In conclusion, the correct trajectory for the steel ball beyond point B is Path 2, where the ball is slightly deflected toward the magnet due to the attractive force exerted by the magnet.