A balloon is rising vertically upward with a constant speed of 15\,m/s. When the balloon is 60\,m above the ground, a ball is released from it. Neglect air resistance and take g=9.8m/s2.
(i) Taking the upward direction as positive throughout, calculate the time taken by the ball to reach the ground.
(ii) Now choose the downward direction as positive for the same motion and repeat the calculation of the time of fall, showing all working steps.
(iii) Comment on your results obtained in parts (i) and (ii), emphasising the importance of consistency in sign conventions.