GeoGebra

29 May

Template for self-assessment questions

Seng Kwang Tan GeoGebra 0 Comments

Here is a template that I might use to generate questions for students’ self-assessment in future. Based on a query that one of the participants in a GeoGebra online tutorial asked about generating random questions for simple multiplication for lower primary students.

The online tutorial was conducted by some teachers in the Singapore MOE GeoGebra community to share how GeoGebra could be used to create resources for home-based learning.

24 May

Angular velocity

Seng Kwang Tan 06 Motion in a Circle, GeoGebra 0 Comments

This GeoGebra app shows how angular velocity ω is the rate of change of angular displacement (i.e. $\omega=\dfrac{\theta}{t}$) and is dependent on the speed and radius of the object in circular motion (i.e. $v=r\omega$).

Students can explore the relationships by doing the following:

Keeping r constant and varying ω.

Keeping ω constant and varying r.

Keeping v constant by varying r and ω.

24 May

Angular displacement

Seng Kwang Tan 06 Motion in a Circle, GeoGebra 0 Comments

This GeoGebra app shows the relationship s = rθ.

One activity I get students can do is to look at the value of θ when the arc length s is equal to the radius r. This would give the definition of the radian, which is the angle subtended at the centre of a circle by an arc equal in length to its radius.

Mathematics defines the constant π as the ratio of a circle’s circumference to its diameter. This can also be shown in the app, although you need to drag the moving point to a point just short of one full revolution.

08 May

Creating a simple interactive using GeoGebra

Seng Kwang Tan GeoGebra 0 Comments

While preparing to share with some fellow teachers in Singapore about the use of GeoGebra in Physics, I came up with a set of simple instructions to create an interactive, while introducing tools such as sliders, checkboxes (along with boolean values) and input boxes. Download it here.

You should be able to follow the instructions in the pdf document above and make a simple interactive applet yourself too. The outcome of the interactive applet will be like this:

19 April

Forces in Equilibrium

Seng Kwang Tan 04 Forces, GeoGebra, IP3 04 Forces 0 Comments

While preparing for a bridging class for those JAE JC1s who did not do pure physics in O-levels, I prepared an app on using a vector triangle to “solve problems for a static point mass under the action of 3 forces for 2-dimensional cases”.

For A-level students, they can be encouraged to use either the sine rule or the cosine rule to solve for magnitudes of forces instead of scale drawing, which is often unreliable.

For students who are not familiar with these rules, here is a simple summary:

Sine Rule

If you are trying to find the length of a side while knowing only two angles and one side, use sine rule:

$$\dfrac{A}{\sin{a}}=\dfrac{B}{\sin{b}}$$

Cosine Rule

If you are trying to find the length of a side while knowing only one angle and two sides, use cosine rule:

$$A^2 = B^2 + C^2 – 2BC\cos{a}$$

08 April

Using Loom and GeoGebra to explain a tutorial question

Seng Kwang Tan 04 Forces, GeoGebra, Loom 0 Comments

It’s Day 1 of the full home-based learning month in Singapore! As teachers all over Singapore scramble to understand the use of the myriad EdTech tools, I have finally come to settle on a few:

  1. Google Meet to do video conferencing
  2. Google Classroom for assignment that requires marking
  3. Student Learning Space for students’ self-directed learning, collaborative discussion and formative assessment.
  4. Loom for lecture recording
  5. GeoGebra for visualisation

The following is a video that was created using Loom to explain a question on why tension in a rope on which a weight is balanced increases when the rope straightens.