Technology

30 March

Sky-Diving and Terminal Velocity

Seng Kwang Tan 02 Kinematics, GeoGebra, IP3 02 Kinematics 0 Comments

https://www.geogebra.org/m/wavar9bx

This is a wonderful applet created by Abdul Latiff, another Physics teacher from Singapore, on how air resistance varies during a sky-dive with a parachute. It clearly demonstrates how two different values of terminal velocity can be achieved during the dive.

Incidentally, there is a video on Youtube that complements the applet very well. I have changed the default values of the terminal velocities to match those of the video below for consistency.

Also relevant is the following javascript simulation that I made in 2016 which can show the changes in displacement, velocity and acceleration throughout the drop.

28 March

Potential Divider with Thermistor Applet

Seng Kwang Tan 15 DC Circuits, GeoGebra, IP4 12 DC Circuits 0 Comments

The wonderful thing about GeoGebra is that you can whip up an applet from scratch within an hour just before your lesson and use it immediately to demonstrate a concept involving interdependent variables. I was motivated to do this after trying to explain a question to my IP4 students.

The RGB colours of the thermistor reflects the temperature (red being hot, bluish-purple being cold)

https://www.geogebra.org/m/etszj23m

This was done to demonstrate the application of potential dividers involving a thermistor and a variable resistor. It can, of course, be modified very quickly to introduce other circuit components.

17 March

Newton’s 2nd Law Applet

Seng Kwang Tan 03 Dynamics, GeoGebra, IP3 03 Dynamics 0 Comments

For a full-screen view, click here.

<iframe scrolling="no" title="Dynamics Problem" src="https://www.geogebra.org/material/iframe/id/uthszwjq/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/true/ctl/false" width="640px" height="480px" style="border:0px;"> </iframe>

This applet was designed with simple interactive features to adjust two opposing forces along the horizontal direction in order to demonstrate the effect on acceleration and velocity.

12 February

Equation of Motion App

Seng Kwang Tan 02 Kinematics, GeoGebra, IP3 02 Kinematics 0 Comments

Access the app in full screen here: https://www.geogebra.org/m/mfvvhjrj

This app is designed to give students practice in interpreting velocity-time graphs with various scenarios, such as more complex examples involving negative velocity and acceleration. Answers will be given if student is wrong.

Use this to embed into SLS or another LMS.

<iframe scrolling="no" title="Equations of Motion" src="https://www.geogebra.org/material/iframe/id/mfvvhjrj/width/700/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="700px" height="480px" style="border:0px;"> </iframe>

03 February

3D Virtual Experiment – Simple Pendulum

Seng Kwang Tan 10 Oscillations, GeoGebra, IP4 Practical, Simulations 2 Comments

This is a simple virtual experiment with a 3D view, allow teachers to explain the simple concepts of an oscillation experiment, such as which view is best to measure timing of the oscillation from.

To access this simulation directly via GeoGebra, go to : https://www.geogebra.org/m/d3yxgjfp

To embed it in SLS or other platforms, use the following code:

<iframe scrolling="no" title="Pendulum" src="https://www.geogebra.org/material/iframe/id/d3yxgjfp/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/true/ctl/false" width="640px" height="480px" style="border:0px;"> </iframe>
26 December

3D Virtual Experiment on Torsional Pendulum

Seng Kwang Tan 10 Oscillations, GeoGebra, Simulations 0 Comments

In preparation for HBL in 2022, I designed a simple virtual experiment that will allow for students to collect data on oscillations using their own stopwatches and investigate the relationship between the period of oscillation and two separate variables. To access the simulation on GeoGebra, visit https://www.geogebra.org/m/jhc4xvpe.

Based on the given relationship $$T = cm^aL^b$$ where a, b and c are constants, students will be tasked to find the constants a, b and c. Students will then attempt to “linearise” the equation such that the independent variables m and L can be tested one by one.

Examples of data collected can be plotted using Excel to give the following graphs from which the gradients and vertical intercepts can be obtained instantly.