Important Laws

☞⊙Lens Law:-
"The direction of an induced current is always such that it opposes the cause that produce it".

☞⊙Faradys Law:-
"The induced e.m.f produce in a closed circuit is directly proportional to the time rate of change of flux. "
☞€ proportional  △Q/△t

☞⊙Joules Law:-
"Amount of heat energy generated in resistance due to flow of electric current is equal to the product of square of current I,the resistance R and time duration t."
☞W=I^2Rt

☞⊙Fleming left hand rule:-
"Fleming stretch the thumb,forefinger and middle finger of the left hand which were perpendicular to each other and if forefinger shows direction of magnetic field and middle finger shows direction of current then thumb indicates the direction of force acting on the conductor."

⊙Snells Law:-
When ray of light enters from ane particular medium  to other then ratio of sine of angle of incidence to the sine of angle of refraction is constant.
☞⊙Mathematicaly:-

    n= sine i /sine r

⊙Ohm's Law:-

"The current passing through any crossection of a conductor is directly proportion to the applied potential difference provided,the physical state of the conductet is not changed."

☞⊙Mathematicaly:-

V proportional to I

V=IR

Where 'R' is the constant of proportionality and is called ,the resistance of the conductor.

⊙Weber fechner law:-

"The loudness of sound is indirectly proportional to the log10 of intensity of sound."
☞⊙Mathematicaly:-
If 'I' is the intensity of sound then the loudness of sound is
L proportional log10 I
L=K log 10 I

⊙Law of Conservation of Momentem:-

The momentem of an isolated system of two ormorethantwo interacting bodies rmains constant.

☞⊙Mathematicaly:-

  MV + mv =0

Or

  MV = - mv

Hence

  V= - m/M × v

⊙Law of Gravitation:-

Everybody in the universe attracts every other body with a force which is directly propottional to the product of their masses and inversely proportional to the square of the distance between their centres.

☞⊙Mathematicaly:-

   F=G ( m1m2 / d^2 )

⊙Pascals Law :-

Pressure applied at any point af a liquid enclosed in  a container, is transmitted without loss to all other parts of the liquid.

⊙Archimedes Principle:-

When an object is totally or partially immersed 

In a liquid, an upthrust acts on it equal to the weight of the liquid it displaces.

⊙Principle of floatation:-

A floating object displaces a fluid having weight equal to the weight of the object.

⊙Hooke's Law:-

The strain produced in a body by the stress applied to it ,is directly proportional to the stress within the elastic limit of the body .

☞⊙Mathematicaly:-

  Stress proportional strain

  

  Stress = constant × strain

  Stress/strain = Constant