We normally think that dissipative forces tend to decrease the velocity of an object. This is correct

Question:

We normally think that dissipative forces tend to decrease the velocity of an object. This is correct for isolated systems. Consider the case of an artificial satellite of mass \(m\) in a circular orbit of radius \(r\) around the Earth. Because of friction with the Earth's atmosphere, the radius of the orbit decreases very slowly by a quantity \(\Delta r\) as it approaches the surface. Determine: \((i)\) the change in velocity \(\Delta v\) due to the change in the radius of the orbit; (ii) the corresponding change in kinetic energy \(\Delta T\) and potential energy \(\Delta V\); (iii) the work \(\Delta W\) done by the frictional forces. Recall that \(\Delta r