15 terms

Radiation Physics

The study of stationary or resting charges
- A connection made to the earth
- Ground potential is zero
- Process by which electrons are added or removed from a body
Methods of Electrification
Terms of Electrostatics
Electrification by Friction
-Transfer of electrons from one object to another by rubbing
-The object gaining electrons becomes negatively charged
-The object losing electrons becomes positively charged
Electrification by Contact
-Occurs when two objects touch, permitting electrons to move from one to the other. A simple equalization of charges with both objects having similar charges after contact.
Electrification by Induction
-A process of electrical fields acting on one another without contact.
-Utilizes metallic conductors.
-Every charged body is surrounded by a force field called an electric field.
Laws of Electrostatics
Laws of Electrostatics
Repulsion-Attraction: Like charges repel
Unlike charges attract
-The inverse square law
-Like charges repel, Unlike charges attract.
The inverse square law
The force between two charges is directly proportional to the product of their magnitude , and inversely proportional to the square of the distance between them.
Charges reside on the external surfaces of conductors
-Only negative charges (electrons) move along solid conductors
-Positive charges are charged atoms which do not drift in solid conductors.
-The greatest concentration of charge is on the surface where the curvature is greatest.
-Electric charges tend to concentrate in the region of sharpest curvature.
Static Discharge
-When two oppositely charged objects are in close proximity, the electrons often jump the gap in the form of a stable discharge.
-Occurs as soon as the difference in charges becomes sufficiently great and the intervening distance sufficiently small. In most cases the static discharge releases excess energy in the form of light photons and an audible sound.
-The cause of tree-branch artifact on a finished radiograph