A stone is released from rest from the top of a tower that is 80m high.
Solve the following using two different sign conventions:
(a) downward taken as positive,
(b) upward taken as positive.
a. (i) Calculate the time taken by the stone to reach the ground level in each convention.
b. (ii) Determine the velocity of the stone just before impact in each convention, clearly indicating the sign.
c. (iii) Comment on the numerical values and signs obtained in parts (i) and (ii). Explain why the physical results are identical even though the algebraic signs differ.