8. The figure below shows how to empty water from a large tank into a low
lying container using rubber tubing:
a
B
С
A
2 m
t..
D
(a) Explain why the tube must
be filled with water before the
emptying process starts.
(b) Soon after the tank begins to empty,
the lower end is momentarily
blocked by placing a finger at
end D. Determine the pressure
difference between points A and
D. (Take density of water to be
(1000 kgm )
ri​

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.