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2018 Stage3 T1 - ELECTRICITY (Physical World)

NESA 2018 SCIENCE: OUTCOMES

A STUDENT (Read more...)

NESA 2018 SCIENCE: CONTENT

ELECTRICAL CIRCUITS (Read more...)

ENERGY FROM A VARIETY OF SOURCES (Read more...)

LIGHT FROM A SOURCE (Read more...)


TEACHER BACKGROUND INFORMATION

Formative Assessment

While teaching we want to collect evidence and data as to how the students are understanding the material. We then use that evidence to form or change what we do next. This process is commonly referred to as Formative Assessment

Formative assessment can take many shapes, including:

Formative assessment is NOT designed to obtain a score for entry into a grade-book.

A well recognised, research-based diagnostic tool (QUIZ) is available to aid formative assessment. At the top of each QUIZ, you will see something like:

THIS IS A QUIZ - IT IS NOT A TEST
It is to help you find & understand correct answers, not mark you down for incorrect answers!

As a bonus, the evidence from 'pre' versus 'post' quiz scores provides an easy way for teachers to gain authentic comments for student reports.

To get started, all teachers and students should first complete the our school ELECTRICITY QUIZ - before commencing any teaching/learning activities.


'Quite simply, if a learner’s thinking is superficial biased, weak, lacking depth or breadth then his learning will be superficial, biased, weak, and lacking depth or breadth. Thinking and learning are inextricably linked' - Lane Clark 1)

Video: MIT Introduction to 8.02 Physics Electricity & Magnetism (5min)


UNDERSTANDING ELECTRICITY

QUIZ: Please complete the on-line ELECTRICITY QUIZ now.

This quiz should be completed on commencement of the course and may be completed one or more times for pre and post-test use.

Getting the 'correct' answers is unimportant - It is only a diagnostic tool to test for understanding.

INTRODUCTION:

This unit (Electricity ST3 2018) is designed to teach the core principals and to ensure students gain an understanding of electricity at the deepest level. It is not an easy topic and it is not easy to teach.

Taking the harder path is justified by the belief that it is better to teach something that is difficult and correct than something that is easier but incorrect.

Video: What holds our world together? - Professor Walter Lewin (MIT) (2min)


SCIENCE:


LITERACY:


EXAMPLE DESIGN + ASSESSMENT TASK:


CONCEPTS:

Each discussion starts with one or more misconception(s) about electricity:

Students will be asked to explain their current thoughts about:

  1. Where does electricity come from?
  2. How is electricity made?
  3. Does electricity move quickly or slowly?
  4. What is an electricity generator?
  5. What is an electric motor?
  6. What is a battery?
  7. What is a conductor?
  8. What is an insulator?
  9. What is a circuit (how does energy get from the battery into the light globe)? 2)
  10. What is a semi-conductor?
  11. What is a switch?
  12. What is a light?
  13. How 'safe' is electricity?

Following these discussions, students are challenged by hands-on activities designed to allow them to discover answers that will assist them overcome any misconceptions about electricity and circuits.

PRACTICAL WORK

The on-line ELECTRICITY QUIZ should be completed on commencement of the course and may be completed one or more times for pre and post-test use.

The teacher/facilitator will explain that students will work together in groups to build electronic circuits.

Students may use on-line resources to experiment and create virtual circuits, investigate Faraday's Law and experiment with electro-magnetism (may require Google CHROME browser)!

Students must ensure that their circuit includes all four parts of a simple circuit:

  1. Power Source -(a battery)
  2. Conducting Path - (wire(s), foil or similar)
  3. Switch - (mechanical device/foil pressure switch to turn device on/off)
  4. Load - (apply power to a device or activate a lamp/LED).
    1. If using a LED:
      1. Demonstrate that a LED only lights when connected one way to power source
      2. A LED is semiconductor. Semiconductors only conduct electricity under certain conditions.

It is extremely important that students come up with their own solutions and answers.

Teacher(s)/facilitator(s) MUST NOT provide prescriptive explanations, strategies or answers during practical activities. Students are encouraged to work collaboratively to come up with their own theories and solutions.

Students must be given continuous opportunities/reminders to compare 'what I used to think' with 'what I think now'

EXAMPLE ACTIVITY - BUILDING A PUPPY SWITCH

Video: RESTRICTED - LPS Electricity - 5/6 Awesome Design & Make a 'Puppy Switch' (2min)

Another example of what was done at our school in 2017, where our school students interview students from other schools who presented their science projects at the MAAS Young Creators Conference 2017

Video: our school Splice Savers at the Young Creators Conference 2017 (4min)


LINKS TO RELATED QUESTIONS, ANSWERS & RESOURCES:

The on-line ELECTRICITY QUIZ should be completed on commencement of the course and may be completed one or more times for pre and post-test use.

ELECTRICITY:

Video: Electricity (Explanatory TV Documentary Style) Bill Nye (6min)


Most textbooks forget to mention where electrical energy comes from

QUESTION(s) Where do you think electricity and electrical energy comes from?


BATTERIES:

Video: Batteries - ABC Catalyst TV Documentary - Watch first few mins (Total 29min)


Most textbooks forget to mention how batteries have changed and why they are so important for the future

QUESTION(s) Do you think batteries store electricity?


ELECTRICAL CIRCUITS:

Video: Symphony of Science - Ode to The Brain (Complex Electrical Circuits)


Many textbooks forget to mention a quite important example of an electrical circuit - the human brain:

QUESTION(s) Do you think the human brain may be like an electrical circuit - or not?


HOMEWORK - LESSON 1

HYPOTHESES & QUESTION(S):

  1. When you build a house, all of the electricity is already in the wire. The electricity company does not make, supply or sell any electricity.
  2. When you buy a battery, all of the electricity is already in the battery and never gets used up. Batteries do NOT store electricity.
  3. What is a switch?
    1. Can electricity travel through a switch that is turned 'off' (travel through an open circuit)?

YOUR FINDINGS/ANSWERS:

  1. Where do you look first for answers (for example; friends, teachers, parents, Internet)?
  2. Were you surprised by anything that you discovered through research?
  3. Have any of your ideas changed? What did you used to think and what do you think now?

WHAT MOST TEXTBOOKS SAY (about electricity)

Many encyclopaedias, dictionaries, and textbooks tell the wrong story about the nature of electricity. They often say something like this:

  1. Electricity is a type of energy.
  2. Electric current is a flow of energy.

The above (and any similar statements) are wrong.

  • Yes, electrical energy does exist. However, this energy cannot be called electricity.
  • Yes, electrical charge does flow in the wires. However, this flow cannot be called electricity and it is not electrical energy.

WHAT MOST SCIENTISTS SAY (about electricity)

The term electricity (like chemistry) refers to an area of science. To avoid confusion, scientists prefer to only use the word electricity for the purpose of general conversation as the common use of the word 'electricity' means many different things to different people.

SCIENTIFIC EXPERIMENTS HAVE SHOWN THAT (Read More...)


HELICOPTER CHALLENGE

Students will work in groups to design a helicopter ignition switch - A circuit designed to activate a 'helicopter'

Before take-off, students need to perform three 'pre-flight take-off checks' and a fourth switch for take-off.


FOR OUR CLASSROOM CHALLENGE (Read More...)


Video: LPS Helicopter, pre-take-off checks


THE LPS AIRFORCE 'HELICOPTER IGNITION SWITCH' CHALLENGE (Read More...)


ADVANCED

Richard Feynman on School Science Textbooks

'Everything was a little bit ambiguous – they weren't smart enough to understand what was meant by “rigor.” They were faking it. They were teaching something they didn't understand, and which was, in fact, useless, at that time, for the child.' - Source: 6)

Albert Einsten on Electricity

If you're swayed by authorities, then listen to Albert Einstein, from his 1938 book Evolution of Physics:

“The electric fluid flowing through the wire is the negative one, directed, therefore, from lower to higher potential… The next important question is whether the structure of this negative fluid is “granular,” whether or not it is composed of electric quanta. Again a number of independent experiments show that there is no doubt as to the existence of an elementary quantum of negative electricity. The negative electric fluid is constructed of grains, just as the beach is composed of grains of sand, or a house built of bricks. This result was forumlated most clearly by J. J. Thomson, about forty years ago. The elementary quantity of negative electricity are called electrons.” - Einstein/Infeld, EVOLUTION OF PHYSICS 1938, p 253

So even Einstein believes that “electricity” is not electromagnetic energy, but instead is the same as Charge (it is Coulombs rather than Joules.) 7)

REFERENCES

3)
Scientific definition of Electricity - http://amasci.com/miscon/maxwell.html
4)
The Water/Wave analogy is an imperfect but useful aid to help promote entry-level understanding of electrical fields
6)
Judging books by their covers - http://www.textbookleague.org/103feyn.htm
7)
Einstein about electricity - http://amasci.com/miscon/maxwell.html#max