Tag Archives: National 5

applications of satellites⤴

from @ fizzics

By now you should have watched the video about satellites.  This screenshot showing a satellite passing over the Highlands was taken from about 17 minutes into the programme – did you notice at the time?               It was quite eye-opening to see just how much modern society relies on ... Read more applications of satellites

re-entering the atmosphere⤴

from @ fizzics

In space there is no air resistance to oppose motion, so the Space Shuttle orbiter could travel at very high speeds, up to 17,000 mph!  At these speeds, the orbiter experienced enormous air resistance as it descended into the Earth’s atmosphere at the end of its mission. Air resistance is just like any other form ... Read more re-entering the atmosphere

x-rays⤴

from @ fizzics

X-rays are a form of electromagnetic radiation.  They have a much higher frequency than visible light or ultraviolet.  The diagram below, taken from Wikipedia, shows where x-rays sit in the electromagnetic spectrum. image by Materialscientist Wilhelm Röntgen discovered x-rays and the image below is the first x-ray image ever taken.  It shows Mrs. Röntgen’s hand and wedding ring.  ... Read morex-rays

dosimetry: absorbed dose and equivalent dose⤴

from @ fizzics

This week, we’ve looked at calculating radiation doses.  The absorbed dose D, measured in Grays (Gy), takes into account the energy E absorbed and the mass m of the absorbing tissue. The higher the energy, the greater the absorbed dose.  If you are wondering why the absorbing mass is important, consider the different masses of ... Read moredosimetry: absorbed dose and equivalent dose

geiger-müller tube⤴

from @ fizzics

We’ve examined the operation of a Geiger-Müller counter as part of the radiation topic. image by Theresa Knott The Geiger-Müller (GM) counter is used to detect ionising radiation such as alpha and beta particles or gamma rays.  The radiation enters through a very thin window at one end of the tube.  This window is usually made ... Read moregeiger-müller tube

x-rays⤴

from @ fizzics

X-rays are a form of electromagnetic radiation.  They have a much higher frequency than visible light or ultraviolet.  The diagram below, taken from Wikipedia, shows where x-rays sit in the electromagnetic spectrum. image by Materialscientist Wilhelm Röntgen discovered x-rays and the image below is the first x-ray image ever taken.  It shows Mrs. Röntgen’s hand and wedding ring.  ... Read morex-rays

total internal reflection⤴

from @ fizzics

Earlier this week, we used semi-circular perspex blocks to investigate total internal reflection. I’ve put together a short video showing total internal reflection in a semicircular block and a perspex model of an optical fibre. total internal reflection from mr mackenzie on Vimeo. There are some nice ray diagrams explaining total internal reflection on BBC ... Read moretotal internal reflection