Which is correct statement?
(1) The entropy of the universe increases
and tends towards the maximum
value
(2) All natural processes are irreversible
(3) For reversible isolated processes,
change of entropy is zero
(4) For irreversible expansion of
isolated processes, entropy change < 0
Show that volume of a region
of space bounded by a boundary
surface S is V= (1/3)∫∫_(S ) rcos θdA .
θ being the angle between the
position vector of a point P on
the surface, and the outer normal
to the surface at P.
r is the distance of point P from
origin.