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Markus Artner BG Neunkirchen. ELECTRIC FIELD AND FORCE. Introduction. Short Description: Students will find out about electric forces in easy set up experiment. A museums visit will enable students to have an idea of what kind of electric phenomena nature can bring up
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Markus Artner BG Neunkirchen ELECTRIC FIELD AND FORCE
Introduction • Short Description: • Students will find out about electric forces in easy set up experiment. • A museums visit will enable students to have an idea of what kind of electric phenomena nature can bring up • Students study phenomena by observing simulations and videos • Age range: 15-16 years old • Context: School, museum • Time required: approx. 5-7 lessons • Connection with the curriculum: electric force, coulombs law, electrostatic phenomena
Eliciting Curiosity – pre visit phase 1 How can a scrap of paper on a table be lifted without touching it? The scrap can be lifted by using frictional electricity of a charged ruler A balloon is prepared as being charged by frictional electricity and attached to the glass of the window. As it stays there some questions will appear: what kind of force makes the balloon being fixed? Students have to find the similarity to the first experiment
Questions Eliciting Activities – pre visit phase 1 Define questions from current knowledge What do we know about charge Who found out characteristics about charged and defined them (historical background)? Material
Questions Eliciting Activities – pre visit phase 1 Define questions from current knowledge What kind of forces do we already know? Where do those forces come from? One of those forces are caused by electric charge: what forces appear with 2 like charges and 2 unlike charges? What happens to charges in conductive material and what to those in insulators? Material
Pre Visit –Phase 2: Active Investigation – PROPOSE PRELIMINARY EXPLANATION OR HYPOTHESES How can we set up an easy experiment to measure and compare charge? Get some ideas from current knowledge: in everyday life anyone knows charges are "produced" by taking off woole textiles or similar. Find out how to "produce" electric charged objects Find out forces that appear
Pre Visit –Phase 2:plan simple investigation Build your own electroscope • Using simple devices to explore electric field strenght • Development of scientific models for measuring Balloon, can and foil Charged balloons
Pre Visit –Phase 2:propose preliminary hypothesis • Identification of possible misconceptions associated to electricity. Some could be: • Electric charged objects attract because of magnetic force: This can easily be disproved by simple experiments • Protons move from object to object: Misconception associated to the structure of matter: This would need a deeper repeating of matter-theory • Electric force increases and decreases direct proportionally to distance. This misconception can be used to start investigation by the help of electric field animation
Pre Visit –Phase 2:Observation: Electric field simulation • View field line grid • analyze influence of additional charged particles • measure forces and strength • View forces as vector graphs Animation
Pre Visit –Phase 2:Observation: Charges and field simulation • View field line grid • analyze influence of additional charged particles • measure forces and strength • View forces as vector graphs
Pre Visit –Phase 2:Investigation: How does electric force depend from distance and charge? • Use of worksheet • Analyze different charges • Analyze different distances • Measure field strenght • Protocol measurements and report worksheet
Pre Visit –Phase 2:Observation: Play electric field hockey • Try to reach the goal • Mind the attracting and repelling force • Try to use as less charge as possible start game material
Visit - Phase 3Creation – GATHER EVIDENCE FROM OBSERVATION • The high voltage room at the technical museum in Vienna • Observe experiments showing the impact of high voltage electric fields • Observe the tesla coile and emerging flashovers http://www.tmw.at/default.asp?id=216&al=deutsch
Visit - Phase 3Creation – GATHER EVIDENCE FROM OBSERVATION • Students observe phenomena of high voltage • Students observe emerging flashovers that appear at the tesla coil http://www.tmw.at/default.asp?id=216&al=deutsch
Visit - Teaching Phase 4Discussion – Explanation based on evidence • What could be a possible explanation for lightening in nature • The teacher points out that earth and clouds carry a huge amount of charge. • Students discuss how can the charge of clouds be produced.
Visit - Teaching Phase 4Discussion – consider and observe explanations based on animations: moving icy and fluid particles in clouds
Visit - Teaching Phase 4Discussion – Explanation based on evidence • How do electric fields take influence on our life • Considering: high voltage lines, electric plugs • What could be an explanation for lightening http://www.tmw.at/default.asp?id=216&al=deutsch
Analyzing – post visit Teaching phase 5: communicate observations and explanations What do we know about electric phenomena in everyday life and how can we know there are electric fields? Students are asked to make reports of observation Students are enforced to start the coulombe-quiz How does earths and atmospheres electricity work out? working out explanations for the phenomena Students work out presentation using material from the web Discuss presentations and findings start quiz material