The water drops fall at regular interval from a tap 5 m above the ground. The third drop is leaving the tap at instant the first drop touches the ground. How far above the ground is the second drop at that instant ?
See figure. Let t be the time interval between any two drops.
For third drop
For second drop
or
Therefore h = 5 - x = 5 - 1.25 = 3 . 75 m