The fundamental Laws of Physics

1. Newton’s  Laws of Motion
            Newton's three laws of motion, govern the motion of physical objects. They define the fundamental relationships between the acceleration of an object and the forces acting upon it.

First Law:     A body continues in its state of rest or of uniform motion along a straight line 
        unless that state is changed by an external force. 

Second Law: The rate of change of momentum of a body is directly proportional to the                     resultant force acting on the body.

Third Law:    For every action in nature there is an equal and opposite reaction. 

2. Law of Conservation of momentum
            The total momentum of an isolated system remains conserved. If there are no external forces acting, then the sum of the momenta of all compnents of a system remains constant. The vector sum of the momenta of all the objects of a system cannot be changed by interactions within the system.  
            
3. Law of conservation of energy
            Energy can neither be created nor destroyed but it can be transformed from one form to another. Since energy cannot be created or destroyed, the amount of energy present in the universe always remains constant.
        
4. Law of conservation of Mass and Energy
    In 1905  Albert Einstein announced his discovery of the equation E = mc2.. This implies that mass and energy are interconvertable. As a consequence, we have the general law called the Law of Conservation of Mass-Energy:
        The total amount of mass and energy in the universe is constant.

5. Law of conservation of mechanical energy    
        If there are only conservative forces acting on a an object or system, then its mechanical energy remains conserved. (Mechanical energy is the sum of kinetic and potential energies.)

6. Law of Universal Gravitation
         Isaac Newton's groundbreaking work in physics was first published in 1687 in his book "The Mathematical Principles of Natural Philosophy," commonly known as "The Principia." In it, he outlined his theory about gravity . His  law of gravity states that:

     Objects attract each other with a force directly proportional to the product of the masses of the objects and inversely proportional to the square of the distance between them. 

7. Kepler's Laws 

    1)Each planet revolves round the Sun in an elliptical orbit with the Sun at one focus. 

    2)The straight line joining the Sun and the planet sweeps out equal areas in equal             intervals of time. 

    3)The squares of the orbital periods of planets are proportional to the cubes of the semi-        major axis of their elliptical trajectories around the sun.

8. Laws of Thermodynamics
    
Zeroeth Law of Thermodynamics 
        If two systems are separately  in thermal equilibrium with a third system, then             the two systems are in thermal equilibrium with each other. 
    The Zeroeth Law of Thermodynamics defines the notion of temperature.

First Law of Thermodynamics
        When a certain amount of heat enters a system, a part of it is used for increasing             the internal energy of the system and the remaining is used for doing work
    The First Law of Thermodynamics demonstrates the relationship between internal energy,             added heat, and work done by a system. It is a statement of conservation of energy.
Second Law of Thermodynamics
        The second law of thermodynamics states that the total entropy of an isolated                 system can never decrease over time, and is constant if and only if all processes             are reversible. 
Third Law of Thermodynamics
        The Third Law states, “The entropy of a perfect crystal is zero when the tem                perature of the crystal is equal to absolute zero (0 K).

9. Stefan’s Law 
    The total energy radiated from a black body is proportional  to the fourth power of its         absolute temperature.
10. Wien’s displacement law

Wien’s law is a relationship between the temperature of a blackbody and the wavelength at which it emits the most light.

    Wien's displacement law states that the black-body radiation curve for different tem            peratures will peak at different wavelengths that are inversely proportional to the             temperature

11. Newton’s law of cooling

    The rate of heat loss of a body is directly proportional to the difference in the tempera        tures between the body and its surroundings, provided this difference is not too large.

12. Hooke’s Law 
    For a solid body, within proportional limit, stress is directly proportional to strain.
The law implies that the extension of a spring is proportional to the force stretching it. 

13. Pascal’s Law 
    Any excess pressure applied to a fluid is transmitted undiminished to all parts of the             fluid and to the walls of the container.

14. Bernoulli's Principle
    As the speed of a moving fluid (liquid or gas) increases, the pressure within the fluid             decreases.

    It is expression of the conservation of energy for any incompressible flowing fluid in terms of its pressure, velocity, density, and vertical height.

15. Archimedes Principle
    When a body is partially or totally immersed in a fluid, it experiences an upward thrust         equal to the weight of the fluid displaced by it.  
    i.e. its apparent loss of weight is equal to the weight of liquid displaced.

16. Boyles's Law
    Temperature remaining constant, volume of a given mass of a gas varies inversely with         the pressure of the gas.

17. Charles's Law
    The volume of an ideal gas at constant pressure is directly proportional to the absolute         temperature.

18. Avagadro’s Law
    Equal volume of all gases under the same conditions of temperature and                 pressure contain equal number of molecules.

19. Dalton’s Law
    The total pressure exerted by a mixture of gases is equal to the sum of the partial pres        sures of the gases in the mixture.

20. Graham’s Law
    The rates of diffusion of gases are inversely proportional to the square roots of their             densities under similar conditions of temperature and          pressure.

21. Coulomb's Law
    The force of interaction  between two point charges is directly proportional to the             magnitudes of the charges and inversely proportional to the square of the distance             between them. 

22. Gauss's Law 
    The net outward electric flux   through a closed surface is proportional to the net                  electric charge enclosed by the surface. 

23.Ohm's Law
    The electric current passing through a conductor between two points is directly propor        tional to the potential difference across the two points 

24. Ampere’s law
    The line integral of magnetic field around a closed loop is proportional to the net elec        tric current passing through any surface enclosed by the loop

25. Faraday’s law of induction, 
    Whenever the magnetic flux linked with a coil changes, an emf is induced in it. The             induced emf is directly proportional to the rate of change of magnetic flux linked with         the coil.

26. Hubble’s Law
    For distant galaxies, redshift in the spectra is directly proportional to their distance.