NUCLEAR & ATOMIC

Links checked 13th January 2010

LOWER SCHOOL

Here is a very simple Rutherford scattering with a nuclear atom.  With the slit reasonably wide this is quite a nice simulation of Rutherford scattering. This is an excellent Rutherford Scattering applet.

The simple display of nuclei radioactively decaying with a plot of the number left, is useful.

Alpha decay is here shown nicely, linked to half-life. One nucleus can be 'watched' as time passes. Beta decay is done in the same way.

The Radioactive Dating game is very good.

Beta decay is here shown as diagonal moves on the n-p plot.  Simple but graphic.

Lots of chains of radioactive decay; this beautiful applet enables you to select a parent isotope at the start of a radioactive decay chain, and then watch, on the Z/N chart (unfortunately the 'wrong' way round) as the decay chain unfolds.  Hovering over each isotope gives relevant information on it.

A decay chain, which you can step down.

This shows the workings of an ionisation-type smoke alarm nicely.

A simple simulation of a chain reaction.

Start a chain reaction, or introduce non-radioactive isotopes to prevent one. Control energy production in a nuclear reactor! Great simulations!

Nuclear power plant.  Stop it blowing up...

This is a clever one. Choose a gas, it displays its emission spectrum, and under it a trial spectrum area, and a section where you can put in energy levels, and transitions, which, if they are in the right frequency range, are displayed to compare with those of the actual element. Nice stuff!  This is the same, but just for Hydrogen.)  

UPPER SCHOOL

Physics 2000, a useful site for modern Physics.  Some good movies and animations (Ian Yems)

The IBM web site has a gallery with a collection of stm images of single atoms etc including the quantum corral, complete with standing electron de Broglie waves. (Rick Marshall) 

This is a beautiful simulation of electrons orbiting a proton/nucleus. You launch your electron at your speed and direction, and it will go into orbit - if you get it right. You can have several running at the same time - and they electrostatically interact with each other.

How about this Photoelectric effect with a quite detailed drawing of the experiment using a variable stopping voltage? You can change the frequency of the incident light, and then adjust the stopping voltage - you see the current fall as the voltage rises. When you get the voltage (only as a stopping voltage, not the other way round!) to be sufficient, a point is plotted on an appropriate graph.  This one is helpful, because you can have the voltage both ways round, and you can vary the intensity; it shows I, V, material, intensity, but again no movement - no photon! And here's a third photoelectric effect, very nicely done - the stopping voltage affecting the electrons is beautiful.

How did Rutherford figure out the structure of the atomic nucleus without looking at it? Simulate the famous experiment in which he disproved the Plum Pudding model of the atom by observing alpha particles bouncing off atoms and determining that they must have a small core.

How did scientists figure out the structure of atoms without looking at them? Try out different models by shooting photons and alpha particles at the atom. Check how the prediction of the model matches the experimental results.

What a nice simple idea to have the orbits of the Hydrogen atom with an electron that can be moved from one level to the next, and then changed from a moving particle to a wave! (It gives the energy in J and eV, and the radius)

Bohr atom with energy levels, orbits, and lines produced.  You select the orbital, and the transition occurs.

Showing the production of light from a discharge tube, starting from thermionic emission.

Here is an excellent collection of resources in short videos, including, for example, the move from the plum pudding atom, via Rutherford, to Bohr.

This shows the visible emission and absorption spectra of most elements. This is a clever one: choose a gas, it displays its emission spectrum, and under it a trial spectrum area, and a section where you can put in energy levels, and transitions, which, if they are in the right frequency range, are displayed to compare with those of the actual element. Nice stuff!  (This is the same, but just for Hydrogen.)  Here is the twin brother, which shows absorption spectra.

Here is a laser explanation showing the atoms becoming excited etc.

Interference of electrons is beautifully shown here; the 2-slit pattern gradually appears. Here is another cartoon version on YouTube.

A home movie of the 1927 Solvay conference, showing all the great physicists involved in the Electron/Photon debate.

{For wave-particle duality, as it applies to electrons in atoms, there is every reason to extend into some of the concepts of Schrodinger's equation.  This site seems particularly good.}

The strange world of quantum mechanics by Daniel F Styer is worth a look.

Here's an animated cyclotron. Here's a clear diagram of a linear accelerator. And here's an animated very simple linear accelerator.

Particles

The Particle Adventure is a great site for learning about Particle Physics

Build a carbon atom starting from quarks and electrons.  I like this one.

The Large Hadron Collider CERN.

Particle tracks shown and explained; very useful.