What I learned in the past one or two weeks was nuclear physics, which is basically the study of subatomic structures and radioactivity. I learned that the atom is made of electrons, protons, neutrons, and a lot of space. The nucleus of the atom is made of protons and neutrons which is kept together by the strong nuclear force while electrons circle around the nucleus in orbitals. The atom is made mostly of space, and the radius can be found using R=1.2fm*A^1/3. Radioactivity occurs when the atom emits rays that carry energy. These rays are different into three types: alpha, beta, and gamma. An alpha particle has the same mass of a helium atom but with a +2 charge. A beta particle has the same mass as an electron but can have either a +1 charge or a -1 charge. And finally, a gamma ray is basically light with an extremely high frequency and of the three is the most dangerous and can kill.
Two topics related to nuclear physics is fission and fusion. Fission occurs when an atom’s nucleus breaks down into smaller ones. Often U-235 is used in fission reactors and can generate usable energy. Fusion occurs when nuclei are fused together to create a bigger nucleus. The sun does this and creates helium out of hydrogen and releases a lot of energy. Another topic is radioactive decay. This is occurs when an unstable atom destroys part of it mass to emit radiation . This is often measured in 1/2 lives, which is the amount of time for half of the atoms to decay to a more stable form. This can be seem graphically as exponential decay. While this doesn’t happen too often in physics, there is also exponential growth. This happens when something growths at a exponential rate. For example, in my picture I just kept doubling the amount of rice I have and it grew tremendously
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Kevin Physics 2 Blog 