What does the returned value of the Line Tracking Sensor indicate when detecting light surfaces?

The Line Tracking Sensor is designed to detect differences in light intensity between the surface it is measuring and its surrounding environment. When the sensor is over a light surface, it registers a high light intensity reading because light-colored surfaces reflect more light compared to darker ones. This high intensity reading indicates the presence of a light surface, which allows the robot to determine its position relative to this surface and navigate accordingly.

In contrast, low light intensity readings would occur when the sensor is over a dark surface, which absorbs more light rather than reflecting it. An undefined value would not apply in this context since the sensor is specifically designed to provide readings based on surface reflections. A constant neutral value is also not applicable as the sensor output varies based on the surface detected. Thus, the high light intensity reading when detecting light surfaces indicates proper functionality and confirmation of what the sensor is designed to do.