This document outlines several laws and theorems from physics including: - Kennedy's theorem which states that the I-center of three plane bodies in relative motion must lie on a straight line. - The zeroth law of thermodynamics which describes thermal equilibrium between systems. - Newton's laws of motion including the first law on inertia, the second law relating force and acceleration, and the third law on action-reaction forces.

2. Kennedy’s Theorem
If three plane bodies have relative motion among
themselves, their I-centre must lie on a straight
line.

3. Law Of Gearing
For constant angular velocity ratio of two gears,
the common normal at the point of contact, of
the two mating teeth must pass through the pitch
point.

4. Zeroth Law Of Thermodynamics
When two systems are each in thermal
equilibrium with a third system, then the two
systems are also in thermal equilibrium with one
another.

5. First Law Of Thermodynamics
O The heat and mechanical work are mutually
convertible.
O The energy can neither be created nor
destroyed though it can be transferred from
one form to another.

6. Second Law Of Thermodynamics
According To Kelvin-Planck
It is impossible to construct an engine working in a
cyclic process, whose sole purpose is to convert heat
energy from a single thermal reservoir into an
equivalent amount of work.
According To Clausius Statement
It is impossible for a self acting machine, working in a
cyclic process, to transfer heat from a body at a lower
temperature to a body at a higher temperature without
aid of an external agency.

7. Boyle’s Law
The absolute pressure of a given mass of perfect
gas varies inversely as its volume, when the
temperature remains constant.
PV=constant

8. Charles’ Law
The volume of a given mass of perfect gas varies
directly as its absolute temperature, when the
absolute pressure remains constant.
V/T=constant

9. Gay-Lussac Law
The absolute pressure of a given mass of a
perfect gas varies directly as its temperature,
when the volume remains constant.
P/T=constant

10. Joule’s Law
The change of internal energy of a perfect gas is
directly proportional to the change in
temperature.
dE = mcdT

11. Newton’s First Law
Everybody continues in state of rest or of
uniform motion in a straight line unless it is
compelled by an external agency acting on it.

12. Newton’s Second Law
Rate of change of momentum of a body is
directly proportional to the impressed force and
it takes place in the direction of the force acting
on it.

13. Newton’s Third Law
For every action there is an equal and opposite
reaction.

14. Newton’s Law Of Gravitation
The force of attraction between any two bodies
is directly proportional to their masses and
inversely proportional to square of the distance
between them.

15. Law Of Transmissibility Of Force
According to this law the state of rest or motion of
the rigid body is unaltered if a force acting on the
body is replaced by another force of same
magnitude and direction but acting anywhere on the
body along the line of action of the replaced force.

16. Triangle Law Of Forces
If two forces acting simultaneously on a body
are represented by the sides of a triangle taken in
order, their resultant is represented by the closing
side of the triangle taken in the opposite order.

17. Parallelogram Law Of Forces
If two forces acting simultaneously on a body at
a point are represented in magnitude and
direction by the two adjacent sides of the
parallelogram, their resultant is represented in
magnitude and direction by the diagonal of the
parallelogram which passes through the point of
intersection of the two sides representing the
forces.

18. Varignon’s Theorem
The algebric sum of the moments of a system of
coplanar forces about a moment centre in their
plane is equal to the moment of their resultant
force about the same moment centre.

19. Lami’s Theorem
If a body is in equilibrium under the action of
three forces, each force is proportional to sine of
the angle between the other to forces.

20. Perpendicular Axis Theorem
The moment of inertia of an area about an axis
perpendicular to its plane at any point is equal to
the sum of moments of inertia about any two
mutually perpendicular axis through the same
point and lying in the plane of the area.

21. Parallel Axis Theorem
Moment of inertia about any axis in the plane of
an area is equal to the sum of moment of inertia
about a parallel centroidal axis and the product
of area and square of the distance between the
two parallel axis.

22. Hook’s Law
Stress is proportional to strain upto elastic limit,

23. Fourier’s Law Of Heat Conduction
The rate of flow of heat through a simple
homogeneous solid is directly proportional to the
area of the section at right angle to the direction
of heat flow, and to change of temperature with
respect to the length of the heat flow.

24. Wien’s Law
The wavelength corresponding to the maximum
energy is inversely proportional to temperature
of the body.

25. Kirchhoff’s Law
The emissivity of the body at a particular
temperature is numerically equal to its
absorptivity for radiant energy from body at the
same temperature.

26. The Stefan-Boltzmann Law
The emissive power of black body is directly
proportional to fourth power of its absolute
temperature.

27. Lambert’s Cosine Law
Total emissive power from a radiating plane
surface in any direction is directly proportional
to the cosine of angle of emission.

28. Pascal’s Law
Pressure or intensity of pressure at a point in a
static fluid is equal in all directions.