View Single Post
 Thanks for the reply tiny-tim :) The fact that in an inertial frame, $\ddot{r}$ is positive is what bothers me ... How can the block, physically speaking, move if there is no force responsible for its radial motion ? I understand your point mathematically but I still have some trouble understanding it intuitively :/ And also, what is the meaning of the block having a zero radial acceleration component while it is still moving radially ? Again, the mathematics of it make sense to me, but its physics is what confuses me the most ... What is the real meaning of radial acceleration ?