When thinking about atoms, one of the obvious puzzles is how a nucleus stays together when it is packed with positively charged particles (protons). Why don't the positive protons simply repel each other, causing the nucleus to disintegrate? The fact that there are also neutral particles (neutrons) in the nucleus may “dilute” the positive charge … Continue reading What is the Strong Nuclear Force?
Hideki Yukawa and Meson Theory
How does the nucleus of an atom stay together? Why don’t the positively-charged protons repel each other and cause the nucleus to disintegrate? The early models of the atom imagined solid spheres, perhaps with different sizes, shapes or “colours” distinguishing one type of atom from another. Then came J J Thomson’s discovery of the electron … Continue reading Hideki Yukawa and Meson Theory
Atoms: Key Facts
There's an old science joke: "you should never trust atoms because they make up everything". And that's true. Atoms aren't liars (as far as I know) but they are the smallest parts of all substances. But what else are you expected to know? Firstly, atoms are really small. The diameter of a typical atom is … Continue reading Atoms: Key Facts
Rutherford’s Gold Foil Experiment
Ernest Rutherford is credited with proving that atoms have a small, dense and positively charged nucleus surrounded by negatively charged electrons. To be exact, it was Ernest Marsden who carried out the very first version of the famous gold foil experiment while working under the direction of Rutherford and Hans Geiger. Rutherford was not even … Continue reading Rutherford’s Gold Foil Experiment
Black Holes
In our course, we cover Black Holes only as the final product of a collapsed super-massive star but if you want to know more about these fascinating objects then I highly recommend the ten-minute video by Perimeter Institute. To view the video, go to https://www.youtube.com/watch?v=TfdviKnUZOA&list=PL1608DAAD37A04B35 The same collection of videos also has a great six-minute … Continue reading Black Holes
Mr Tarrant's physbang 'blog 