The Earth completes one full rotation on its axis in approximately 24 hours. To calculate the rotational speed of the Earth per second, we can divide the total number of seconds in a day (24 hours x 60 minutes x 60 seconds = 86,400 seconds) by the time it takes for one rotation:
86,400 seconds / 24 hours = 3,600 seconds
Therefore, the Earth rotates at a speed of approximately 3,600 seconds per rotation, or 0.25 degrees per second.