I did the ticker tape experiment. Made a ramp, attached ticker tape to the end of a cart, thread the tape through the ticker timer, let the cart roll down the ramp ^.^'' My question; lets say my ramp had an imperfection, like a bumb or groove. How would that show up on my ticker tape? What would it look like? And also the experiment was designed to compensate for the effect of friction. Can you explain how this was done?