the world in a different light
This GeoGebra app is a 3-D visualisation tool of the force vectors acting on an aircraft turning with uniform circular motion in a horizontal plane.
I prepared this in advance as I will be lecturing on this JC1 topic next year.
The following GeoGebra app simulates a pressure sensor that measures hydrostatic pressure, calibrated to eliminate the value of atmospheric pressure.
The purpose of this simulation is to address certain misconceptions by students such as the assumption that the shape of a container affects the pressure such that the pressure differs in different containers when measured at the same depth.
Drag the dot around to compare the pressure values at the same height between both containers.
The following codes can be used to embed this into SLS.
<iframe scrolling="no" title="Hydrostatic Pressure" src="https://www.geogebra.org/material/iframe/id/wbjduxt7/width/640/height/480/border/888888/sfsb/true/smb/false/stb/false/stbh/false/ai/false/asb/false/sri/true/rc/false/ld/false/sdz/false/ctl/false" width="640px" height="480px" style="border:0px;"> </iframe>This app is used to demonstrate how a spherical object with a finite volume immersed in a fluid experiences an upthrust due to the differences in pressure around it.
Given that the centre of mass remains in the same position within the fluid, as the radius increases, the pressure due to the fluid above the object decreases while the pressure below increases. This is because hydrostatic pressure at a point is proportional to the height of the fluid above it.
It can also be used to show that when the volume becomes infinitesimal, the pressure acting in all directions is equal.
The following codes can be used to embed this into SLS.
<iframe scrolling="no" title="Hydrostatic Pressure and Upthrust" src="https://www.geogebra.org/material/iframe/id/xxeyzkqq/width/640/height/480/border/888888/sfsb/true/smb/false/stb/false/stbh/false/ai/false/asb/false/sri/false/rc/false/ld/false/sdz/false/ctl/false" width="640px" height="480px" style="border:0px;"> </iframe>The recently launched Apple AirPod Pro presents a wonderful opportunity to relate an A-level concept to a real-world example – how noise-cancelling earphones work.
Apple’s website explained it in layman terms that seem to make sense. Let your students attempt to do a better job of explaining how destructive interference of waves is applied.
I probably won’t spend SGD379 on it though.
I was looking for an extension to the Micro:bit Go set that I bought a while back and came across a robot set that is currently on sale. This set comes with most of the sensors a typical line following or obstacle avoiding robot needs. Currently, it is being sold at a fraction of the price of other similar Micro:bit robots, and is far cheaper than sets such as the Lego EV3.
After unpacking it earlier this evening after work, I managed to put together the parts by following the instructions, which were quite clear.
To program the robot using Micro:bit’s Makecode, which is a block programming interface that is very similar to Scratch, you will need to download the Yahboom blocks by selecting Extensions from the Advanced menu.
Enter the following URL into the search bar: https://github.com/lzty634158/yahboom_mbit_en
You will then see the library of new blocks including those meant for the robot below:
A few simple lines of code are all that is needed for the light sensors to keep tracking a black line by turning whenever one of the sensors detect white while the other detects black.
After programming the robot, download the hex file into the Microbit and the robot is good to go.
https://www.seriouslyscience.sg/one-north-Festival/Overview
Happening now from 13-14 Sept 2019 at one-north.
My colleagues and I took the opportunity to visit the exhibitions during lunch time today. I learnt about 3M’s solar films and retroreflection material, I^2R’s speech-to-text recognition app with code switching capabilities (i.e. the app is able to transcribe English-Chinese mixed sentences) and cell-based prawn meat from https://shiokmeats.com/, among other things.
There was also an informative booth on Project Wolbachia (where male aedes mosquitoes infected with Wolbachia bacteria are released into the wild to control the population). I learnt that they could separate the male from the females at the pupal stage because male pupals are larger and got to stick my hand in a box full of male Wolbachia-Aedes mosquitoes.
