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Question:

A person in a lift is holding a water jar, which has a small hole at the lower end of its side. When the lift is at rest, the water jet coming out of the hole hits the floor of the lift at a distance of 1.2m from the person. In the following, the state of the lift's motion is given in List I and the distance where the water jet hits the floor of the lift is given in List II. Match the statements from List I with those in List II and select the correct answer using the code given below the lists.
List I
List II
P. Lift is accelerating vertically up. 1. d=1.2m
Q. Lift is accelerating vertically down with an acceleration less than the gravitational acceleration. 2. d>1.2m
R. Lift is moving vertically up with constant speed. 3. d<1.2m
S. Lift is falling freely. 4. No water leaks out of the jar

P-2, Q-3, R-1, S-4

P-2, Q-3, R-2, S-4

P-1, Q-1, R-1, S-4

P-2, Q-3, R-1, S-1

Solution:

Velocity of efflux V=√2geff where l is length of jar from top of point.
time taken in covering horizontal distance is T=√2h/geff, where h is distance of floor from jar
Horizontal range = VT = √2geffl √2h/geff = √4lh which is independent of geff.
In free fall velocity of efflux will be zero.