Xray

pic taken from euronuclear.org
The spectrum of emitted radiation reaches from a maximum energy given by the kinetic energy of the generating particle down to zero energy. Bremsstrahlung only becomes easily noticeable when the energy of the particle is very high compared to its self-energy. This is mostly only valid for electrons (self-energy of the electron: 511 keV).

Picture that speaks for itself

Upon the collision of a particle and an anti-particle, e.g. electron and positron, these are "annihilated" as particles and the mass of these particles converted into energy. Electron and positron have a rest mass which is together equal to an energy of 1.02 MeV. Upon the "annihilation" of both particles, two gamma quanta of 0.511 MeV each are generated...adapted from euronuclear.org

Electron-positron annihilation

Diagram of electron–positron annihilation, producing 2(511 keV) photons leaving in opposite directions.How to find the photon energy ? Use Einstein s mass energy relation as 2 equal mass electron/positron produce 2 photons means one electron produce one photon. E= mass of electron x speed of light square. Two photons are produced as conservation of momentum is necessary.
If reverse can occur , what photon energy can produce a electron-positron pair?

Electron energies in atoms

The emission spectra of atoms provides the proof of the quantum theory as it applies to atoms and subatomic particles. Every element can be made to emit light that is characteristic for that element. This is consistent with the idea that each element has a unique energy level pattern. The light emitted by an element's atoms matches the possible jumps betweeen energy levels for the electrons in the atoms. extracted from 800mainstreet.com

Types of spectra from different gases

This applet shows you how the three different spectrum can be observed. you tubedhere

Quantum tunneling

You tubed here

Uncertain about what?

Light can be considered as being made up of packets of energy called photons. To measure the position and velocity of any particle, you would first shine a light on it, then detect the reflection. On a macroscopic scale, the effect of photons on an object is insignificant. Unfortunately, on subatomic scales, the photons that hit the subatomic particle will cause it to move significantly, so although the position has been measured accurately, the velocity of the particle will have been altered. By learning the position, you have rendered any information you previously had on the velocity useless. In other words, the observer affects the observed.

adapted from bbc
you tubed here

Emission and Absorption spectrum

pic taken from:http://snews.bnl.gov/popsci/spectroscope.html
Emission takes place in the dark otherwise you cant see the emitted photons. A spectrometer will diffract it to different angles to distinguish the wavelength emitted showing lines
Absorption by gas takes place if light of continuous freq are available I.e white light.The missing lines are due to photons taken away by the gas .
The lines in emission and absorption correspond because the energy levels involved in the two processes are the same.

REd shift /blue shift

pic taken from:http://snews.bnl.gov/popsci/spectroscope.html
When body is moving away from viewer you see a red shift , most common.The dark lines becomes lower in frequency i.e shifting towards the red end of spectrum.
When body is moving towards the viewer you see a blue shift, not so common.

Position momentum uncertainty

When the position is a vertical straight line(x) , the momentum is infinity . When light is a particle , the wavelength is uncertain ( no specific colour)using de broglie formula
When the momentum is a vertical straight line, the wavelength is a single colour but the position is infinity. When a particle has wavelike property, it cannot be found and behaves like a wave having specific wavelength .

The landscape of nanoscopic world

For the curious ones: here is a link to a gallery with video when you got time to kill.
taken out of : www.nanoscience.com/education/gallery.html

Electron as a particle or wave in tunneling

pic taken from :www.nanoscience.comQuantum mechanics tells us that electrons have both wave and particle like properties. Tunneling is an effect of the wavelike nature.
The top image shows us that when an electron (the wave) hits a barrier, the wave doesn't abruptly end, but tapers off very quickly - exponentially. For a thick barrier, the wave doesn't get past.

The bottom image shows the senario if the barrier is quite thin (about a nanometer). Part of the wave does get through, and therefore some electrons may appear on the other side of the barrier..Read more here: nanoscience

Electron tunneling

When the two atoms are close to each other , it is as though they share the electron .If you are very close to your neighbour, there is a probability of me finding you in your neighbours house !Read more at link here : http://www.insp.upmc.

Uncertainty principle

Quantum cops story link here :
pic from saint gasoline.com