Challenging secondary students to learn about physical laws
One of my publications is
Taber, K. S. (2011). Patterns in nature: challenging secondary students to learn about physical laws. Physics Education, 46(1), 80-89. https://doi.org/10.1088/0031-9120/46/1/010
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Abstract
Teaching about the nature of science is seen as a priority within science education, and has also been highlighted as a suitable context for challenging the most able ('gifted') learners at secondary school level. This article discusses a practical session designed to introduce the idea of physical (natural) laws. The session asks students to explore patterns in three physical systems–capacitor discharge, cooling, and equilibration of pressure in two joined columns of water. These activities were chosen because they could all be conceptualized in terms of feedback cycles and exponential decay, and so had potential to show how similar patterns are found in diverse physical phenomena. The session was taught as part of an after-school enrichment programme for 14-15 year-old students who were nominated as 'gifted' by their city comprehensive schools. The session is reviewed in the light of student responses, which suggested that it made suitable demands for the most able students. The session also has potential, with suitable modifications in teaching approach, to contribute to teaching about the nature of science to students of a range of abilities and ages.
Keywords:
- nature of science
- physical laws
- gifted students
- enrichment material
- scientific models and theories
- feedback cycles
- practical work
This article reports work undertaken in relation to the Gatsby SEP funded ASCEND (Able Scientists Collectively Experiencing New Demands) project
"The session was organised around three simple practical activities:
• a capacitor discharge circuit;
• cooling of some heated water;
• water in two connected columns which could be adjusted to give an initial difference in height of water column."
Taber, 2011, p.81
"It was decided to introduce students to the notion of feedback cycles because understanding feedback in systems is a key idea that is applicable across the sciences."
Taber, 2011, p.82
"The material about radioactive decay provided an analogy with the three physical systems to be investigated. In each case, the physical process (radioactivity; current flowing from the capacitor; cooling of hot water; flow of water until water height in the two columns were equilibrated) reduced the 'driver' (number of unstable nuclei p.d. across discharge circuit; excess temperature over ambient background; pressure difference).
As the magnitude of the process was proportional to the magnitude of the driver, the process–in reducing the driver–in effect reduced its own magnitude. Mathematically these can all be considered as exponential decays: and so they can also be conceptualized as systems with negative feedback cycles.
Taber, 2011, p.83
"The parallels between analogous laws found in different areas of physics offers an insight into the nature of the physical world; and the activity discussed here provides a way of demonstrating this without formal mathematics. This allows the work to be carried out by students who have not met the maths (as here). It is also a useful approach because it has been argued that students' learning of physical concepts is improved when they show good qualitative understanding of physical concepts, before they are taught the associated mathematical formalisms"
Taber, 2011, pp.87-88
Read more about the activity here
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