What do you mean by camera motion tracking for 30 seconds and 40 seconds?

Represents the shutter speed. The shorter the time, the less the light.

For example, 1/40S (seconds) is less than 1/30S (seconds).

The faster the shutter speed, the clearer the high-speed moving object is captured. On the contrary, the slower the shutter speed, the more blurred the captured high-speed moving object.