Physics 11–12 · Year 12
De Broglie matter waves: electron diffraction rings and the wavelength of an accelerated electron
Module 8: From the Universe to the Atom (Quantum Mechanical Nature of the Atom)
Teacher-led demonstration
A teacher carries out this activity as a demonstration. Its materials, steps, variables, misconceptions and sources are not published on the open web, and neither is any result, control or note that states a number or an amount: tutors and administrators read them on the learning platform, with the safety card first. The idea, the hazards and the curriculum references are below.
Open the procedure on the learning platform (tutor or administrator sign-in)
School laboratory, not for home
In a school laboratory, with a teacher supervising, under the school's risk assessment. Not for home.
This site has no interactive model of its own. Where a step or a material names a Concept Studio model, simulation or tool, it has not been built; an external simulation a step names (for example PhET) is not part of this site.
The idea
Electrons passed through a crystal form diffraction rings whose size shrinks as the accelerating voltage rises, exactly as a wave of wavelength h over m v would.
Safety card
Setting: In a school laboratory, with a teacher supervising, under the school's risk assessment. Not for home.
Hazards
- EHT supply to 5 kV
- evacuated tube
- low-level X-rays
Controls
At least one of them states a number or an amount, which may be part of the method, so the controls are shown with the method to tutors and administrators on the learning platform.
Note
High-voltage supplies: teacher-only operation with a current-limited EHT supply, and record the activity in RiskAssess (https://www.riskassess.com.au/); Science ASSIST risk management sheet https://asta.edu.au/resource/ais-risk-management-and-risk-assessment/.
What you should see
It states a number or an amount, which may be part of the method, so it is shown with the method to tutors and administrators on the learning platform.
Curriculum references
The NSW syllabus outcomes and Australian Curriculum v9 codes this activity supports. They are references, not a verified or complete curriculum alignment.
- Physics Stage 6 Syllabus (2017), current: Year 11 until the end of 2026, Year 12 until Term 3 2027PH12-15PH11/12-5PH11/12-6
- Physics 11-12 Syllabus (2025), not yet taught: Year 11 from Term 1 2027, Year 12 from Term 4 2027, first HSC examination 2028PY-12-04PY-12WS-06
- Australian Curriculum v9No Australian Curriculum v9 code is listed.