DIDACTICS MATERIALS AND ACTIVITIES Didactic material 1: Classroom rules: To begin the activity we will watch a video that calls attention and starts the brainstorming with questions about what we have watched. https://www.youtube.com/watch?v=ddvTFgzkS5M https://www.youtube.com/watch?v=9iQg16bEGGM We can ask questions such as: How can we be a "good friend"? What must we do to be supportive when working in groups? Tell me several sentences to ask for help when you need it. We will establish together a classroom rules (Our classroom rules) by "Brainstorming". These are some examples: Try to speak in English always Treat others as you would like to be treated. Respect other people and their property. Laugh with anyone, but laugh at no one. Be responsible for your own learning. Come to class and hand in assignments on time. Didactic material 2: Video for listening comprehension. Watch the video and answer the following questions: http://ed.ted.com/lessons/the-science-of-static-electricity-anuradha-bhagwat https://ed.ted.com/lessons/the-science-of-static-electricity-anuradha-bhagwat You will be able to answer these questions after seeing the video. 1. What happens to an atom if you pull off an electron from it? A It explodes B The atom then has a positive (+) charge C The atom then has a negative (-) charge D The atom acquires no charge and stays neutral 2. Which of the following will usually create static electricity? A Rub a wet rag on a carpet B Rub a coin on a carpet C Rub your foot on a carpet D Rub your hand on a door knob 3. What happens to a material that collects electrons on its surface? A It gets negatively charged B It gets positively charged C It starts sparking continuously D It stays neutral 4. What is the difference between a spark and lightning? A Lightning occurs in summer; sparks in winter B Lightning is just a big spark C Lightning makes noises but sparks do not D Lightning is negatively charged, spark is positively charged 5. How does friction between two materials cause electrons to jump from one and stick to another? A Friction scrapes off electrons from one material and deposits them on the other material B Friction doesn't move the electrons; adhesive forces inside the material pull off the electrons C Friction moves electrons because the material gets a net negative charge D Friction arises because of charge imbalances, which move electrons 6. Explain why for static electricity to occur between two surfaces that are rubbed against each other, one of the materials has to be an insulator. 7. Why is the phenomenon of static electricity observed more in dry, winter months than in hot, humid summer months? Didactic material 3: Fill in the gaps with the words in the box. First, watch the video and then fill in the gaps with the keywords http://www.livescience.com/37206-atom-definition.html Conducting, particles, electricity, electrons, repulsión, unbalanced, attraction, protons | Matter is formed by atoms consisting of negatively charged particles ………….. and positively charged particles ……………. Between these particles, there are forces of …………….or …………….that generate a type of energy called……………. In a balanced atom, the number of protons is equal to the number of electrons. The forces of attraction and repulsion between these …………… are balanced. When this balance is disturbed, the electrical forces become ……………and the electrons are driven by their electrical energy to other atoms in search of new balances. We call this transfer of charges electrical current and it is produced in conducting materials. ……………materials transmit electrical energy across their surface. Electric circuits allow us to use electricity as light or other forms of energy (heat, sound or movement). Didactic material 4: Describing pictures Look at the pictures below and discuss in pairs what you can see in each one. At the end, individually, you have to form in your own notebook what is the best definition or direct current and alternating current, with five examples that you use in your daily life. Sources for the activity: http://physics10aps.blogspot.com.es/2013/09/ac-and-dc.html http://www.explainthatstuff.com/electricity.html http://www.buzzle.com/articles/understanding-the-difference-between-alternating-anddirect- current.html Didactic material 5: Roleplaying In groups of three, read about each of the three main electrical variables in a circuit: voltage, current and resistance. - The number one of the group will be an expert in voltage. - The number two of the group will be an expert in current. - The number three of the group will be an expert in resistance. Firstly, all the experts with the same number will meet up to talk about what they have read in the text about their variable. 1. CURRENT Current (I) is the variable that tells us how many electrons flow through the cross-section of a conductor per unit of time. Its unit of measurement in the International System is the ampere (A). Electrons travel from the negative terminal of the power source to its positive terminal (true direction). However, the direction of the current is taken as the flow of the load from the positive terminal to the negative terminal (conventional direction). 2. VOLTAGE Voltage (V) is the variable that tells us the difference in electrical energy per unit of charge between two points in a circuit. This difference can also be called the electric potential difference, potential drop or electric tension. Its unit of measurement in the International System is the volt (V). 3. RESISTANCE Resistance (R) is the variable that tells us the opposition to the passage of an electric current. Its unit of measurement in the International System is the ohm (Ω). In real life, all of the elements in a circuit have resistance. However, in this unit we will consider the resistance of conductors and power sources to be negligible. Didactic material 6: OHM's law http://www.sengpielaudio.com/calculator-ohmslaw.htm#top http://ed.ted.com/on/LcWnujVv Listen to the video and mark the sentences true (T) or false (F). When we measure current, 6.24 bimillion electrons pass through a point of the wire According this video, an Ampere is a Coulomb per second. Current, Voltage and Resistance are related to one another by Ohm's law. The positive and negative charges inside a battery are created by the protons in the battery Fill in the gaps with the words in the box. Then, answer the question. Difference, resistance, directly, attraction, current, inversely, conductor | Electrical energy is the energy generated by the forces of…………..and repulsion between charged particles. In an electric circuit, electrical energy is generated when the electrons move through the …………..due to the potential ………….across the ends of the circuit. Electrical power measures the energy that is consumed by a load device or delivered by a power source over a certain period. P= E/t= V x I Ohm's law states that the………..in a circuit is………...proportional to the electric potential difference impressed across its ends and…………..proportional to the total………offered by the external circuit. I = V/R With this equation, how we can calculate the other variables by rearranging the equation? MATER Didactic material 7: Classify the following circuits with the help of the text below. SERIES CIRCUIT In a series circuit, the resistors are connected one after the other, so all of the electrical current flows through all of the load devices. There is only one possible path for the current to flow through. The calculation of electrical variables is summarized in the table below, where Rt, It, Vt and Pt refer to the variables of the equivalent circuit. PARALLEL CIRCUIT In parallel circuits, load devises are connected one different branches and the current is split. There are several possible paths for the current to flow through. More electrical current flows in the branch that offers the least resistance. The calculation of electrical variables is summarized in the table below, where Rt, It, Vt and Pt refer to the variables of the equivalent circuit. SERIES-PARALLEL COMBINATION CIRCUITS In series-parallel combination circuits, there are elements in series and elements in parallel. To solve a series-parallel combination circuit, we need to find out which resistors are in series and which are in parallel. Then we can apply the equations for each case. http://fbr-fran.blogspot.com.es/ http://fbr-fran.blogspot.com.es/2018/04/material-aicle.html |