Question

Water drops fall at regular intervals from tap 5m above the ground.The third drop is leaving the tap at the instant the first drop touches the ground.How far above the ground is the second drop at that instant? A ) 1.25m B ) 2.5m C ) 4.25m D ) 2.25m E ) 3.75m

Answer 1

Given:
Height =h=5m
To calculate time taken by first drop to reach ground:
u=0m/s, t=T
so,
s=ut+1/2at²
5=0+1/2aT²-----(1)
Time taken by second drop will be T/2
Therefore, its distance from tap
h=0+1/2(aT²)/4       ------------(2)
divide equ (ii) by equ (1)
h/5=1/4
h=1.25m
therefore H-h=5-1.25=3.75m
Option E is the correct answer.

Answer 2

Given data:
Height =h=5m
s=ut+1/2at²
5=0+1/2aT²-----(1)
Time taken by second drop will be T/2
∴ its distance from tap
h=0+1/2(aT²)/4       ------------(2)
divide equ (ii) by equ (1)
h/5=1/4
h=1.25m
∴ H-h=5-1.25=3.75m
∴ e is the correct answer.