Answer / thiyaga.m.rajan

* The zeroth law of thermodynamics recognizes that if
two systems are in thermal equilibrium with a third, they
are also in thermal equilibrium with each other, thus
supporting the notions of temperature and heat.

* The first law of thermodynamics distinguishes between
two kinds of physical process, namely energy transfer as
work, and energy transfer as heat. It tells how this shows
the existence of a mathematical quantity called the internal
energy of a system. The internal energy obeys the principle
of conservation of energy but work and heat are not defined
as separately conserved quantities. Equivalently, the first
law of thermodynamics states that perpetual motion machines
of the first kind are impossible.

* The second law of thermodynamics distinguishes between
reversible and irreversible physical processes. It tells how
this shows the existence of a mathematical quantity called
the entropy of a system, and thus it expresses the
irreversibility of actual physical processes by the
statement that the entropy of an isolated macroscopic system
never decreases. Equivalently, perpetual motion machines of
the second kind are impossible.

* The third law of thermodynamics concerns the entropy
of a perfect crystal at absolute zero temperature, and
implies that it is impossible to cool a system to exactly
absolute zero, or, equivalently, that perpetual motion
machines of the third kind are impossible

Answer / syam

zerothlaw:if 2 bdies in thermal equilibrium with 3ed body
all 3 bodies in equ.. with each other
1st law:total energy remains constant
Q=i.e+wd
2nd law: cant supply energy from low region to high with aid
of external work

HYDROLICS

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