light

Home » light

Ptolemy – Roman astronomy – history of science

By |2018-04-11T09:22:19+00:00September 4th, 2017|Romans, Science|

A copy of Ptolemy's map of the world Ptolemy was born in Egypt in about 90 AD, when the Romans were ruling Egypt. He was a Roman citizen. Probably he was the son or grandson of a Roman government slave - maybe a clerk - who was freed and got citizenship. As a boy, Ptolemy went to Greek schools in Alexandria and wrote in Greek. When [...]

Galen and Roman medicine – doctors in the Roman Empire

By |2018-04-18T18:18:03+00:00September 4th, 2017|Romans, Science|

Roman medicine: Galen used surgical instruments like these Roman medicine is really West Asian and African medicine. That's because most of the great doctors of the Roman Empire lived in West Asia (in Turkey and Syria), or in Africa (in Egypt), not in Europe. These doctors started from earlier Egyptian, Indian, and Greek medical research. Like Egyptian [...]

Rainbows and water – a sun project

By |2018-05-31T11:49:25+00:00August 18th, 2017|Physics|

Sunshine through the clouds and Earth's atmosphere You can see that the sunlight that reaches the Earth travels at different wavelengths. On a sunny day, put a full glass of water (a real glass glass) in the sunshine on your windowsill. Look where the sunshine goes through the water, and you should see rainbows on the floor or walls. [...]

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 [...]

European science in the 1800s

By |2018-04-16T10:32:30+00:00August 7th, 2017|Modern Europe, Science|

European boys at school in the 1800s In the first half of the 1800s AD, countries in northern Europe like France and Britain forced India, Ghana, Nigeria, Canada, and other countries to give them food. That meant that many people in northern Europe could stop farming and get an education. Families sent more boys to school than girls, so most of the educated people were [...]

Emilie du Chatelet – European philosophy

By |2018-04-08T11:14:27+00:00August 7th, 2017|Modern Europe, Philosophy|

Emilie du Chatelet, a French philosopher in the 1700s Emilie du Chatelet's rich father, who was interested in literature and science, hired tutors to homeschool her, instead of sending her to a convent school. She learned Latin, German, Greek, and Italian, as well as math and science. When du Chatelet was 18, she married [...]

du Chatelet light project – European science

By |2018-04-08T11:14:26+00:00August 6th, 2017|Modern Europe, Science|

Any desk lamp will do You can get colored lights and thermometers and do the experiment that du Chatelet never carried out. See for yourself whether red light will heat things up more than blue light! Get a regular weather thermometer, and set it up under a strong desk lamp so the light shines [...]