physics

In physics we often come across certain laws principles. They are discussed below:

1) Archimedes principle: when a body is party or completely immersed in a fluid it experiences on upward thrust equal to the weight of the displaced fluid.

2) Boyle’s law: At constant temperature the pressure of gas is inversely proportional to its volume.

3) Bernoulli’s principle: when air moves fast parallel to the top surface of any body, pressure of the air above the surface is less than the pressure below that surface. Aeroplanes are able to fly up in air against their own weight on the basis of Bernoulli’s principle.

4) Pascal’s law: an increase of pressure at any point in a liquid at rest is transmitted without change to every other point in the liquid, i.e., equally in all directions.

5) Newton’s law of Gravitation: all particles of matter mutually attract each other by a gravitational force which is directly proportional to the product of their masses and inversely to the square of the distance between them.

6) Lows of reflection of light: when the light rays are reflected by a plane sooth surface 1) the incident ray, reflected ray and the normal drawn at the point of incidence lie in the same plane and 2) the angle of incidence is equal to angle of reflection.

7) Laws of refraction of light: 1) a ray of light passing from a rarer medium into a denser medium is deviated towards the normal at the point of striking the common surface of the two media. When the ray of light passes from a denser medium into a rarer one, the ray is deviated from the normal. 2) The ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant and is called the refractive index of the second medium with respected to the first medium.