ideas to implementation

Mer av detta

ConceptMap

av Cordelia Guerra

CONDUCTORS AND INSULATORS

av Sofia Ricottilli

Radioactivity and Particles

av Hazwan Nadzri

Atoms

av Alan Crooks

Superconductor

Conduction and resistance

Resistance

Conduction

Bragg

outline the methods used by the Braggs to determine crystal structure

Bragg used x-rays (100 ev Photons)

X-rays are made by electrons smashing metals

x-rays reflect of atoms

spaced atoms cause interference

Semiconductor

Production of electrons with light - solar cells

Electron Tube - TV

Applications

•outline the role of:

◦electrodes in the electron gun

◦the deflection plates or coils

◦the fluorescent screen

in the cathode ray tube of conventional TV displays and oscilloscopes

fluorescent screen

Makes light when hit with electrons

Colour TV has clusters of three phosphors for observation at a distance

CrO

Single colour green or blue to read at close distance

Deflection

Old Televisions

External Coils, Cheaper but designed to "RASTER"

Internal E field Plates, Expensive, but highly sensitive for science

Electron gun and Plates

Electron gun has a very high field as the lines converge on a point. Heat also kicks the electrons of the tip.

The acceleration anode give the electrons a high fixed speed, which provides the energy that is later converted into light.

Further Plates act as an electrostatic lens that curves electrons moving at an angle to the axis back into form an image of the gun on the screen.

Old Television

Three guns for three colours, and designed to switch current pixel to pixel

CRO

Single gun, with focus designed for steady intensity.

E B balance e/m

F = Eq...........................................(1)

F =qvB..........................................(2)

F=mv^2/r (with no electric field).......(3)

also E= V/d

(1) = (2) gives v

(2) = (3) + v + r measured gives e/m

or (1) = (2) = (3) gives q/m = E/rB^2

ideas to implementation

The production of electrons through the interaction of light, such as in solar cells, involves various physical principles. Superconductors, materials that exhibit zero electrical resistance, play a significant role in advanced technologies.

ConceptMap

CONDUCTORS AND INSULATORS

Radioactivity and Particles

Atoms