In this illustration, we'll analyze the change
in apparent weight due to breathing. we are
given that a person can change the volume
of his body by taking air into his lungs.
and the amount of change can be determine
by weight, the person, under water. here we
are given if a person underwater weighs 200
newton with partially full lungs. and 400
newton with empty lungs. we are required to
find the change in body volume due to breathing.
here we can write, if volume of body. with.
empty lungs is v, then here we can write body
weight minus v ro g which is the buoyant force
acting on it. should be equal to 400 newton,
as we are already given. that with empty lungs,
the body weight is considered to be 400 newton.
so the effective weight is body weight minus
the buoyant force. here v ro g we are taking
as the buoyant force so this is our first
equation and, we can say, and if, v 1 is,
body volume, with, partially full, lungs.
then here we use, m g minus v 1 ro g should
be equal to 200 newton. that is say second
equation. here if we subtract the 2 1 minus
2 will result. v 1 minus v multiplied by.
ro g is equal to 200, and we know the density
of water as well as g we can substitute so
here v 1 minus v, multiplied by water density
we take as thousand g as 10 this is equal
to 200, here, solving this equation we get
v 1 minus v, is equal to 2 divided by hundred
that is equal to zero point zero 2 meter cube.
that is a result of this problem. the change
in body volume due to breathing in lungs.
