As many know, the atomic bomb has been used only twice in warfare. The first was at Hiroshima. A uranium bomb nicknamed “Little Boy” (despite weighing in at over four and a half tons) was dropped on Hiroshima August 6, 1945. The Aioi Bridge, one of 81 bridges connecting the seven-branched delta of the Ota River, was the target; ground zero was set at 1,980 feet. At 0815 hours, the bomb was dropped from the Enola Gay. It missed by only 800 feet. At 0816 hours, in an instant, 66,000 people were killed and 69,000 injured by a 10-kiloton atomic explosion.
Many thanks to 6th year CBC students for devising these problems.
It’s OK to be Smart host, Joe Hanson, explains how cosmic rays appear to have a longer life than they should because they travel at a speed close to the speed of light (time dilation).
Hanson also builds a Cloud Chamber to view cosmic rays.
Exploring the nature of the atom
• Uranium was discovered in 1789 by Martin Klaproth, a German chemist, and named after the planet Uranus.
• Ionising radiation was discovered by Wilhelm Rontgen in 1895, by passing an electric current through an evacuated glass tube and producing continuous X-rays.
• In 1896 Henri Becquerel found that pitchblende (an ore containing radium and uranium) caused a photographic plate to darken. He went on to demonstrate that this was due to beta radiation (electrons) and alpha particles (helium nuclei) being emitted.
Comic books offer us an insight into the attitudes and beliefs of society at the time. In essence they are a historical document that we can use to determine how people viewed social issues.
The origins of the Hulk (1962) are no different. Below are a few observations of the Hulk origins story that I have made, but have a look at the comic strip first to see if you can pick out the some attitudes reflected in the comic strip. If I’ve missed any, please post them in the comments.
This week marked the 100th anniversary of the start of the First World War. Today marks the anniversary of an even more grotesque event – the dropping of the atom bomb on Hiroshima on 6 August 1945. Three days later the second bomb was dropped on Nagasaki. These remain the only use of nuclear weapons in warfare.
Some 12 km² of Hiroshima were destroyed, as were around 69% of the city’s buildings. The images above, which were taken by the US military on the day, show Hiroshima before and after the bombing. Some 66,000 people are thought to have died in Hiroshima on the day; probably a similar number again died over the next four months as a result of their injuries or from radiation sickness. So fierce was the heat that people were vaporised but their shadows left upon the walls.
In the years since the…
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This is one of those questions that has always bugged me.
Suppose that, somewhere in the universe, there is a very large closed box made out of some kind of heavy, neutral matter. Inside this box a civilisation of intelligent creatures have evolved. They are made out of normal matter like you and me, except that for some reason they are very light — their bodies do not contain much matter at all. What’s more, there are no other heavy bodies or planets inside this large box aside from the population of aliens, whose total mass is too small to have any noticeable effect on the gravitational field. Thus, the only gravitational field that the aliens are aware of is the field created by the box itself (I’m assuming there are no other massive bodies near to the box).
Setting aside the obvious questions about how these aliens came to…
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Seriously! The question in the title is not rhetorical. I cannot really answer the question. All I have is a bunch of ideas on electromagnetism. Anyone has any answers or simply wants to tell me, ‘your ideas are stupid’, please do, in the comments below.
Since the electromagnetic force is propagated by photons, is it possible to detect these photons and measure their characteristics(wavelength for example). Also is there a radiation pressure associated with each photon? Photons can interact with each other, so can the repulsion between 2 electrons be understood as the radiations from both “pushing” one another at the “mid-point” between them?
But if an electron continuously radiates then it should constantly lose mass. But isnt the mass of an electron a fundamental quantity?
Maybe photons given out by electrons are somehow different from those released by positive particles. Every electron while radiating energy into space constantly receives…
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