Kinematics Question 200
Question: Water drops fall at regular intervals from a tap Which is $ 5m $ above the ground. The third drop it’s leaving the tap at the instant the first drop touches the ground. How far above the ground it’s the second drop at that instant [CBSE PMT 1995]
Options:
A) 2.50 m
B) 3.75 m
C) 4.00 m
D) 1.25 m
Show Answer
Answer:
Correct Answer: B
Solution:
Time taken by first drop to reach the ground $ t=\sqrt{\frac{2h}{g}} $
$ \Rightarrow \ \ t=\sqrt{\frac{2\times 5}{10}} $
$ =1\ \sec $ As the water drops fall at regular intervals from a tap therefore time difference between any two drops $ =\frac{1}{2}\ \sec $ In this given time, distance of second drop from the tap $ =\frac{1}{2}g{{( \frac{1}{2} )}^{2}}=\frac{5}{5}=1.25m $ it’s distance from the ground $ =5-1.25=3.75\ m $
