in this example, we are given in a horizontal
pipe line, the flowing oil pressure falls
by 8 newton per meter square, between 2 points,
seperated by 1 km. we are required to find
the change in ki-netic energy per kg of oil
at these points. we are also given the density
of oil to be, 800 kg per meter cube. and here
we can directly write, by using, bernawlli’s
theorem, we have, we can write, as the pipeline
is horizontal we can write, p 1 plus, half
ro v 1 square, is equal to p 2 plus, half
ro v 2 square. as the height level is same,
we can ignore the gravitational potential
energy on both sides of equality. and in this
situation the change in ki-netic energy per
unit volume can be written as, half ro, v
2 square minus v 1 square, this is equal to
p 1 minus p 2, and we are given that, the
pressure difference is 8 newton per meter
square between the 2 points. so we calculate
the change in ki-netic energy per kilogram,
this can be written as half of, v 2 square
minus v 1 square. so we need to divide it
by the density that is p 1 minus p 2 by ro.
so it’ll be 8 by 8 hundred, that can be
given as, zero point zero 1 joule per kg.
that’ll be the answer to this problem.
