A body dropped from the top of the tower covers a distance 7x in the last second of its journey, where x is the distance covered in first second. How much time does it take to reach the ground?

Answer 1

Average velocity in first second = g/2 = 4.9 m/s
Average velocity in 2nd second = 3g/2 = 14.7 m/s
Average velocity in 3rd second = 5g/2 = 24.5 m/s
Average velocity in 4th second = 7g/2 = 34.2 m/s, which is seven times the first second.

It takes 4 seconds.