Question

Drops of water fall from the roof of a building 27m 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 second and third drop from the roof

Answer 1

Answer:

Let the time interval between falling two drops from the roof be t seconds.

Then 4th drop falls after 3t seconds of falling of first drop

∴ The time of flight of 1st drop

=3tsec

H=

2

1

gt

2

9=

2

1

g9t

2

g

18

=9t

2

;t=

g

2

t=

10

2

=

5

1

Distance of 2nd drop from the roof

H=

2

1

g

5

1

=1m or H=

2

1

g(t)

2

Distance of 3rd drop from the roof

H=

2

1

g

5

4

or H=

2

1

g(2t)

2

=4m