Satellites in near-earth orbit experience a very slight drag due to the extremely thin upper atmosphere. These satellites slowly
but surely spiral inward, where they finally burn up as they reach the thicker lower levels of the atmosphere. The radius decreases so slowly that you can consider the satellite to have a circular orbit at all times. As a satellite spirals inward, does it speed up, slow down, or maintain the same speed?
According to my research, a satellite in a circular Earth orbit is subject to a very tiny constant friction force, due to the atmosphere. As it spirals inward, it slowly decreases its orbital radius. So as long as a satellite moves in a circular orbit, it's velocity is inversely proportionate to the square root of the orbital radius-it speeds up as it spirals inward. I hope my answer proves of some help to you.
