SOME PHYSICS LAW

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newton's law of motion

1.Newton first law of motion

A BODY CONTINUES TO BE IN MOTION OR REST ALONG A STRAIGHT  LINE UNLESS A EXTERNAL FORCE IS APPLIED TO IT.

2.Newton second law of motion

THE RATE OF CHANGE OF LINEAR MOMENTUM IS PROPORTIONAL TO THE APPLIED FORCE AND CHANGE IN MOMENTUM TAKES PLACE IN THE DIRECTION THE FORCE IS APPLIED.

3. Newton third law of motion

FOR EVERY ACTION THERE IS AN OPPOSITE AND EQUAL REACTION.

GRAVITATION


NEWTON LAW OF GRAVITATION

THE GRAVITATIONAL FORCE ACTING BETWEEN 2 POINTS OBJECT IS DIRECTLY PROPOTIONAL TO THE SQUARE OF DISTANCE BETWEEN THEM.

KEPLER LAWS OF PLANETARY  MOTION

1. LAW OF ORBIT

EVERY PLANET MOVES AROUND THE SUN IN AN ELLIPTICAL ORBIT AND SUN IS AS ITS ONE FOCUS.

2.LAW OF AREA

THE RADIUS VECTOR DRAWN FROM THE SUN TO THE PLANET SWEEPS OUT EQUAL AREA IN EQUAL INTERVAL OF TIME.

3.LAW OF PERIOD

THE SQUARE OF TIME PERIOD OF REVOLUTION OF A PLANET AROUND THE SUN IS DIRECTLY PROPORTIONAL  TO THE CUBE OF SEMI-MAJOR AXIS OF ITS ELLIPTICAL ORBIT.



ELASTICITY

HOOKE'S LAW

WITHIN THE LIMIT OF ELASTICITY,THE STRESS IS PROPORTIONAL TO THE STRAIN.

HYDROSTATICS

PASCAL'S LAW

THE INCREASE IN PRESSURE AT A POINT IN THE ENCLOSED LIQUID IN EQUILIBRIUM  IS TRANSMITTED EQUALLY IN ALL DIRECTION IN LIQUID AND TO THE WALLS OF CONTAINERS.

HYDRODYNAMICS

STOKE'S LAW

WHEN A SMALL SPHERICAL BODY FALLS IN A LONG LIQUID COLUMN WITH TERMINAL VELOCITY THEN VISCOUS LAW IS ACTING UPON IT.THIS IS KNOWN AS STOKE'S LAW.

SURFACE TENSION

ZURIN'S LAW

IF A CAPILLARY TUBE OF IN SUFFICIENT LENGTH  IS PLACED VERTICALLY IN A LIQUID NEVER COME OUT FROM THE TUBE ITS  OWN.

KINETIC THEORY OF GASES

GAS LAW

ASSUMING PERMANENT GASES TO BE IDEAL , THROUGH EXPERIMENTS,IT WAS ESTABLISHED THAT  GASES IRRESPECTIVE OF THEIR NATURE OBEY THE FOLLOWING LAW.

BOYLE'S LAW

AT CONSTANT TEMP. THE VOLUME OF GIVE MASS OF A GAS IS INVERSELY PROPORTIONAL TO ITS PRESSURE.

CHARLE'S LAW

AT A CONSTANT PRESSURE THE VOLUME OF GIVEN MASS OF GAS IS DIRECTLY PROPORTIONAL TO ITS ABSOLUTE TEMPERATURE.

GAY LUSSAC'S OR RENAULT'S LAW

AT A CONSTANT VOLUME  THE VOLUME OF GIVEN MASS OF GAS IS DIRECTLY PROPORTIONAL TO ITS ABSOLUTE TEMPERATURE.

AVOGADRO'S LAW

HE STATED THAT EQUAL VOLUME OF ALL GASES UNDER SIMILAR CONDITION OF TEMP. AND PRESSURE CONTAINS EQUAL NO. OF MOLECULES.

KIRCHOFF'S LAW

Kirchhoff's law of thermal radiation refers to wavelength-specific radiative emission and absorption by a material body in thermo dynamic equilibrium, including radiative exchange equilibrium.

A body at temprature radiates electro magnetic energy. A perfect black body in thermodynamic equilibrium absorbs all light that strikes it, and radiates energy according to a unique law of radiative emissive power for temperature T, universal for all perfect black bodies. Kirchhoff's law states that:

For a body of any arbitrary material emitting and absorbing thermal electromagnetic radiation at every wavelength in thermodynamic equilibrium, the ratio of its emissive power to its dimensionless coefficient of absorption is equal to a universal function only of radiative wavelength and temperature. That universal function describes the perfect black-body emissive power.

stefan's law of cooling

heat energy emitted per second  per unit are  of a perfectly black body.

 

newton's law of cooling

Newton's Law of Cooling states that the rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature

wien's displacement law

Wien's displacement law states that the black body radiation curve for different temperatures peaks at a wavelength inversely proportional to the temperature.

kirchhoff's law

junction rule:-

This law is also called Kirchhoff's first law, Kirchhoff's point rule, or Kirchhoff's junction rule (or nodal rule).

The principle of conservation of electric charge implies that:

At any node (junction) in an electrical circuit, the sum of currents flowing into that node is equal to the sum of currents flowing out of that node

or equivalently

The algebraic sum of currents in a network of conductors meeting at a point is zero.

Recalling that current is a signed (positive or negative) quantity reflecting direction towards or away from a node, this principle can be stated as:

${\displaystyle \sum _{k=1}^{n}{I}_{k}=0}$

n is the total number of branches with currents flowing towards or away from the node.

This formula is valid for complex currents:

${\displaystyle \sum _{k=1}^{n}{\tilde {I}}_{k}=0}$

The law is based on the conservation of charge whereby the current ( measured in amperes ) is equal to the quotient of charge ( measured in coulombs ) to the time ( measured in seconds ).

loop rule:-

This law is also called Kirchhoff's second law, Kirchhoff's loop (or mesh) rule, and Kirchhoff's second rule.

The principle of conservation of energy implies that

The directed sum of the electrical potential differences (voltage) around any closed network is zero, or:

More simply, the sum of the emfs in any closed loop is equivalent to the sum of the potential drops in that loop, or:

The algebraic sum of the products of the resistances of the conductors and the currents in them in a closed loop is equal to the total emf available in that loop.

Similar to KCL, it can be stated as:

${\displaystyle \sum _{k=1}^{n}V_{k}=0}$

Here, n is the total number of voltages measured. The voltages may also be complex:

${\displaystyle \sum _{k=1}^{n}{\tilde {V}}_{k}=0}$

This law is based on the conservation of energy whereby voltage is defined as the energy per unit charge. The total amount of energy gained per unit charge must be equal to the amount of energy lost per unit charge, as energy and charge are both conserved.