thus in the second second, the ball covers 10m. that’s 30m covered, with a final speed of 5 m/s. that same group realized that for the first 2 seconds, the average speed was 15 m/s for 2 seconds, also giving 30m of travel.
last semester, i had a group solve the problem by finding the speed of a ball dropped 1.25 m/s, arguing on the ground of symmetry that it had to be the same.
we ended the problem this semester by talking about the last 1/2 second, where the ball has an average speed of 2.5 m/s for 1/2 second, thus covering the final 1.25m, and why our guesses for the 