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What makes thunder and lightning? – Weather science

By |2018-04-24T15:20:20+00:00August 20th, 2017|Physics|

A bolt of lightning in the sky Hot air and cold air are constantly moving around the Earth, as the hot air rises and the cold air sinks - that's what makes wind. Sometimes as this airmoves around, it gets more exciting than just wind, though. A thunderstorm begins when the wind picks up a lot of water from the [...]

Radioactivity and nuclear physics

By |2018-04-24T14:44:18+00:00August 17th, 2017|Physics|

A Japanese girl who lost her hair from radiation sickness from the atomic bomb Americans dropped on Hiroshima Some atoms are naturally radioactive, especially atoms of uranium and plutonium. These atoms have so many protons and neutrons that even the strong nuclear force is barely strong enough to hold them together, and they sometimes lose a proton or a [...]

Nuclear fusion – Simple Physics

By |2018-05-31T11:49:26+00:00August 17th, 2017|Physics|

The Sun shining from space Fusion reactions are how the first stars got started. Soon after the Big Bang, hydrogen atoms began bumping into each other and merging into one bigger heliumatom. Four atoms with four nuclei - centers - mixed together into one atom with a bigger nucleus. But each time this happened there was a bit of energy left [...]

Nuclear fission – Physics

By |2018-05-31T11:49:26+00:00August 17th, 2017|Physics|

Nuclear fission: Atomic bomb explosions make a "mushroom cloud" Fission reactions are the kind of nuclear reaction we use for nuclear power plants and nuclear submarines, and also to set off a nuclear bomb. With fission reactions, you take very large atoms like uranium and plutonium and smash them apart into smaller atoms. Because it takes a [...]

Radioactivity and sunburns – Physics

By |2018-04-24T12:26:12+00:00August 17th, 2017|Physics|

Radiation from the sun caused this sunburned back The most common kind of radiation is sunlight, and the most common cause of injury from radiation is a sunburn. Just like radioactivity from a nuclear explosion, radiation from the sun can damage the DNA of your cells. Later the same day, or the next day, your skin may be red and sore. [...]

Nuclear fusion project – Physics

By |2018-05-31T11:49:26+00:00August 17th, 2017|Physics|

Build your own model of a fusion reaction: start with a regular red lego (a proton). Wrap a rubberband around it to be the strong nuclear force. Then connect a small blue lego (an electron) to the red lego to make a hydrogen atom. Make four of these hydrogen atoms. Now imagine that your hydrogen atoms are being heated up [...]

What is a photon? Physics of light

By |2018-05-31T11:49:28+00:00August 16th, 2017|Physics|

Photons - Sunshine breaking through the clouds. When did the first photons appear? A photon is a tiny little particle of light, far too small to see individually. All light is made of photons (FOE-tahns). The earliest photons probably appeared about fifteen billion years ago, during the Big Bang. What's the speed of light? Unlike electrons and quarks, [...]

What is light made of? Why is the sky blue?

By |2018-05-31T11:49:14+00:00August 16th, 2017|Physics|

Rainbow over Amazon river Light is made of billions of tiny particles called photons. These photons travel from one place to another in waves. Visible light is the subset of photons that move at a wavelength that we can see. Among the different photons that are in visible light, the ones that have the [...]