Sunday, October 18, 2009

Electrostatics

Electrostatics is a branch of physics which deals with the study of forces , fields and potentials from static charges.

Eg. -The experience of hearing or seeing a spark while removing our synthetic shirt or nylon sweater usually in dry weather.

      -The sensation of electric shock while opening the door of any car.
    
      -The sensation of shock while holding an iron bar of a bus after sliding from our seat.

      -The metallic bodies cars and trucks get charged due to friction between them and the air passing swiftly rubbing them.This charge  can even produce an spark.

 SOLUTIONS - Petrol tankers usually have a metal chain dragging along the ground.This chain transfers the excess charge on the body to ground.
                      
                       -Now-a-days a carbon compound is added to the rubber tyre.It discharges the excess charge if any to the earth.


Static

Static means something that does not move or change with time.

Charges

Charge is a property of a body due to which two bodies may repel each other.

About Thrust

Also see-Thrust-Definition , fluids

When a fluid is kept at rest in a container its molecules constantly collide with the walls of the container and suffer a change in momentum. 

This change in momentum per unit time constitute a force or Thrust of fluids on the walls of the container.

 A liquid at rest always exerts a constant force or thrust perpendicular to the walls of the container and to the surfaces in contact with it.