Archimedes’ Principle:It states that a body, when
immersed in a liquid, experiences
an upward
thrust equal to the weight of the liquid displaced by it.
Avogadro’s Hypothesis:It is a modification of Berzelius’
hypothesis. It states
that equal volumes of all
gases under similar conditions of temperature
and pressure
contain equal number of molecules.
Boyle’s Law:States that
the volume
of certain
gas is
inversely proportional to the
pressure at a constant temperature. In other words, the product of pressure
and volume remains constant provided the temperature is kept constant
i.e., P x V = a constant,
if T remains the same.
Charles’s Law:It states
that at constant pressure all gases
expand by of their
volume at 0oC i.e.,
the volume of a given mass
of gas
at constant
pressure is directly proportional to the absolute temperature.
Dulong and Petit’s
Law:States that the product
of atomic weight and specific
heat of solid elements is
nearly equal to 6.4 i.e., At. wt. sp. heat = 6.4 approx.
Gay-lussac’s Law of
Combining Volumes:Gases
react together in Volumes which bear simple whole number
Graham’s Law of Diffusion
: States that the rates
of diffusion of gases are
inversely proportional to the square roots of their densities
under similar conditions of temperature and pressure.
Law of Definite Proportions : A chemical compound is always found
to be
made up of the same
elements combined together in the same ratio by weight.
Law of Floatation : For a body to
float, the following conditions must be
fulfilled: (1)The weight of the
body should be equal to the weight of the water displaced.
(2) The centre of
gravity of the body and
that of the liquid displaced should be in the same straight line.
Newton’s Law of Universal
Gravitation : States that “Every portion of matter attracts
or tends
to approach
every other portion of
matter in the universe with
a force proportional to the masses
and inversely
as the
square of the distance”.
Newton’s First Law
of Motion
: A body continues
in its state of rest
or of
uniform motion in a straight line
unless compelled by an external force to change that state.
Specific heat of substance : The quantity of heat required to rise the temperature of 1 gm. of a substance through 1oC.
Newton’s Second Law of Motion :
The rate of change of
momentum is proportional to the impressed force
and takes place in the direction
of the force.
Newton’s Third Law of Motion : To every action,
there is an equal and opposite
reaction, e.g. Rockets, recoil
of a gun.
Newton’s Law of
Cooling : States that the
rate of loss of heat of a hot body is directly proportional to the
difference of temperature
between the body and the surrounding and is independent of the nature of the
body.
Ohm’s Law :
States that the ratio of the potential
difference between the ends
of a conductor and the current flowing in the conductor is constant. e.g., for a
potential difference of E volts and
a current/amperes, the resistance R, in Ohms is equal to E/I.
Principle of Conservation of Energy
: It states
that, in any system,
energy cannot be created or
destroyed; the sum of
mass and energy remains constant
