Question

drops of water fall from the roof of of a building 18m high at regular intervals of time. when the first drop reaches the ground, at the same instant fourth drop begins to fall. what are the distance of the 2nd and 3rd drops from the roof

Answer 1

NOTE 1
drop 1 covers 18m in T(1.9156sec).
when drop1 reaches ground 3 more drops are released.
as time interval between each drop is same(constant).
therefore time interval between each drop is
t,=T/3 =1.915/3
t,=0.638sec



NOTE2
we take drop4 as reference point as it is at roof.
time interval between drp4 and drp3 is t,

same way time interval between drp2 and drp3 is t,
BUT time interval between drp2 and drp4 is 2t,