Students are shown a demonstration of pie tins flying off from the top of a Van de Graaff generator to prove the existence of an electric force. Students are given a challenge to stick a balloon to the wall without using any adhesives. They succeed in doing so by rubbing the balloon with fur. They think why only the side that is rubbed sticks and no the other end, leading to the idea of insulators not able to conduct or move charge within itself.
Students then explore the interaction between charged particles, in a "Sticky Tape Lab" in groups. They observe how two pairs sticky tape ripped off from a table attract or repel each other individually. They also observe the attraction of repulsion between glass and plastic rods rubbed against fur. They tabulate their observation of the interactions, and infer the rules of electrostatic attraction and repulsion. They also draw the idea of two kinds of charges, and are explained the convention of 'positive' and 'negative' to identify these categories. Students then work on an interactive simulation that illustrates charging by induction and conduction.
Students end the class getting shocked with the Van de Graaff generator, getting charged as a chain of students holding hands and discharging on on uncharged student, thereby understanding the role of the human body as a conductor. Students are also assigned an interactive simulation to work on at home and a upload screenshot, that probes their understanding of electrostatics deeper.
Interactive: Charging by Conduction and Induction
Students discuss and share their conclusions from the interactive simulation they were assigned as a warmup. Students are shown a demonstration by the teacher with a Plasma Ball, that enables them to visualize electric field lines. The demonstration includes lighting fluorescent bulbs in the vicinity of the plasma ball, and an illustration of how its intensity reduces with distance. Students see a video where the direction of the electric field around a Van de Graff generator is indicated by a straw on a pivot. Students work on two interactive simulations that lead them from the concept of electrical forces to electrical fields.
Students are provided the equation of Coulomb's Law, introduced with its similarity with Newton's Law of Gravitation. Students discuss answers to practice questions involving Coulomb's Law, as a class discussion.
Video: 10 ways to see an electric field
Interactive: Put the charge in the goal
Charge Hockey: PhET simulation
Students watch a video on balls bouncing down the streets of San Francisco as an engage. Then the students imaging taking a virtual field trip through the streets of San Francisco, and they work in pairs to address questions on gravitational potential at different points on the map, drawing on their prior knowledge of gravitational potential energy. The students understand electric potential as an analogue of gravitational potential, enabling them to understand voltage as difference in electric potential.
Video: Bouncing balls in San Francisco
Electricity: History and Vocabulary: TedEd Video
Students work in pairs perform an activity using a coffee straw and a stirrer, by timing how long it takes to breath out a lung full of air through them. Students observe that the thicker straw as more air flow. Students draw the analogy of 'resistance' in wires with thinner wires having more resistance to current flow. Students repeat the activity with two straws held back to back, and breathing out through two straws in parallel at the same time, and determine it is faster to breathe out through the parallel straws. Analogy is made with series and parallel circuits.
Students measure the voltage and current through a simple series circuit containing one known resistance using a multimeter, and infer the relationship in Ohm's Law. Students then measure the voltage across a bulb in a simple series circuit and determine its resistance using Ohm's Law. Students then perform voltage measurements on series and parallel circuits composed of two resistors, and infer Kirchoff's current and voltage laws using Ohm's Law.
Students practice problems in electric circuits. The solution is presented in the form of Sudoku puzzles.
Students watch the hour long "The Story of Electricity" episode on the history of electromagnetism, from the "Shock and Awe" BBC documentary series. It describes the key players involved, their discoveries and the impact of these discoveries on society.
Video: Shock and Awe: The Age of Invention (Episode 2 - "The Story of Electricity" at 58:00 min)
Students circulate stations to explore different electromagnetic phenomena, including deflection of a compass needle in the presence of a current carrying wire, spinning magnet that carries current through a wire, spinning coils in the presence of an electric field, electric currents produced by moving a magnet inside a coil and by a windmill, and a 'magnet train' consisting of a battery with magnets on both sides moving on its own through a bare copper wire table.
• Explain how generators, motors, and transformers work.
Each student does research on either generators, motors or transformers. Then the experts on each topic get together and discuss as a group. The class is formed in groups of three, with one expert from each topic, and they make a one minute presentation to each other. After a whole class discussion to review the concepts presented, students build a speaker using magnet wire, battery, magnets, wires and the top of a soda bottle.
Students review contents of electromagnetism learned so far, organized as stations for different topics.