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Misconceptions About Temperature

Misconceptions About Temperature
Related:  Physical world (Physics)

Balancing Brooms - finding the centre of mass Listen Now Download as mp3 from the show Should I Lie Down to Tan? What you Need What to do Point the index fingers of both hands and hold your hands apart but parrallel. Get someone to balance the broom horizontally on your two index fingers, making sure you keep them level. Now gently move your fingers together. What may happen You should find that as long as you keep your fingers level the broom stays balanced, even as they get very close together. Why does it happen? When you start off holding the broom inevitably one finger will be closer to the centre of mass than the other. This means that more of the weight will be sitting on the closer finger, so it must be pushing upwards harder. The larger the force between the finger and the broom the larger the maximum frictional force it can provide before it slides. The finger furthest from the centre of mass will therefore be able to slide the most easily, and it moves until it is no longer the furthest from the centre of mass. Dave Ansell Multimedia

Quel Milieu pour l’apprentissage par problématisation en sciences de la vie et de la terre ? 1Les études que notre équipe mène au sein du CREN (Université de Nantes) sur les apprentissages des sciences de la vie et de la Terre (SVT) nous ont conduits à développer un cadre théorique, celui de l’apprentissage par problématisation, en articulant des références à Bachelard et Canguilhem avec des études de cas considérées comme autant d’investigations épistémologiques (voir, par exemple, Orange, 2002, 2005). Ce cadre théorique prend place dans une réflexion plus large sur la problématisation et ses liens avec les savoirs et les apprentissages (Fabre 1993, 1999). 1 Elle dit reprendre ici une distinction proposée par Brousseau en 1997. Dans cette théorie des « sit (...) 2 Pour des raisons pratiques, une partie de nos références et leur pagination renvoient à Brousseau, (...) 3 Des savoirs sont dits apodictiques s’ils présentent, dans un cadre problématique donné, un caractèr (...) 4Plus largement, c’est la référence à l’apprentissage par adaptation de la TSD qui nous pose problème.

Insulation Experiment: Keep Your Body Warm Ever wonder why your mom makes you wear two or three layers of clothing when you want to go outside and build a snowman? These clothes are actually great insulators, which mean they're made from materials that keep your body temperature from dropping. In this insulation experiment, you'll learn which fabrics help keep you warm on an icy winter day. Some weather conditions, such as rain, wind, and snow cause our bodies to lose heat. If you don't select the right materials to keep your body warm and toasty, you'll start to shiver from the cold. Wearing warm, insulating clothes allows you to stay outside even longer, having snowball fights with your friends, creating snow angels, and building igloos to play in. Problem: Which type of fabric insulates heat the best? Materials: 7 glasses of the same size and shape Water Thermometer Wool Cotton Denim Lace Fleece Nylon Kitchen timer Notebook and pencil Procedure: Results: Why? Disclaimer and Safety Precautions

Keep it Cool | TryEngineering Lesson Focus Lesson focuses on the engineering behind keeping food and other items cool. Students work in teams to develop a system to make an insulated liquid container that will keep chilled water as cool as possible for an hour using everyday items. Students will need to devise a way to have a thermometer rest in the water and be able to read the temperature throughout the hour. Age Levels: Objectives Learn about insulation, heat transfer, and vacuums.Learn about engineering design and redesign.Learn how engineering can help solve society's challenges.Learn about teamwork and problem solving. Anticipated Learner Outcomes As a result of this activity, students should develop an understanding of: insulationvacuumheat transferengineering designteamwork Lesson Activities Students explore how engineers have developed systems to keep liquids cool and learn about heat transfer, insulation, and vacuums. Resources/Materials Alignment to Curriculum Frameworks

Les boules ! Physique Qu'est-ce qui tombe le plus vite, un jeu de clé ou une boulette de papier ? C'est à partir de cette question "simple" que les animateurs de l'atelier "physique" mettent au travail leur auditoire. Avis partagés : les clés doivent tomber plus vite, puisqu'elles sont plus lourdes ? On refait l'expérience avec une boule de pétanque, une boule de polystyèrene qu'on a lestée et une balle de tennis qu'on va lâcher à la hauteur de 2,5 mn. Moment de doutes général... mais alors si on supprimait l'air, les objets tomberaient en même temps ? "Il faut d'urgence faire une synthèse magistrale : "si j'ai pas d'air, tout le monde tombe en même temps. "Mais alors... Ultime défi à résoudre... Reprenons : pourquoi ça tombe, finalement ? Mais pourquoi ces deux forces coincident exactement ? C'est le moment de conclure... La gardienne du temps revient pour la troisimèe fois : les plateaux-repas sont servis...

The Science of Heat (Children's Encyclopedia of Science): 6. Rays of Warmth Stand outside on a warm summer day and you can feel the Sun's heat on your face. But how does it reach you? There is nothing but 93 million miles of empty space between the Sun and the Earth. Heat can only travel by conduction or convection where there is matter. To cross empty space, it must move by a different means. Heat radiation, like light, consists of waves. Heat Rays and Matter The amount of heat radiation soaked up by a substance depends on what type of substance it is. A material that reflects light like a mirror, such as metal foil, will also reflect most of the heat waves that strike it. A Trap for Sunlight Glass will let both light waves ad heat waves from the Sun pass easily through it. This is how a greenhouse works. The Earth: A Giant Greenhouse Some gases work like the glass in a greenhouse. One of the problems at present is that many human activities produce large amounts of carbon dioxide.

Inspire Her Mind Science There’s a young 4-year old girl shuffling through a chest full of various dress-up clothes. The copy asks: Does dress-up determine her future? Scroll to the left, and the girl picks up a princess dress from the chest. She walks over to a mirror and holds the dress in front of her. The girl in the mirror, representative of her imagination, is wearing the dress and holding a wand. Scroll to the right, and the girl picks an astronaut suit out of the chest. Technology There’s a father and daughter working on an electronic helicopter. Scroll to the left, and the father takes a soldering iron and starts working on the helicopter while the daughter watches. Scroll to the right, and the daughter reaches forward to connect a wire on the helicopter, making it work, as the rotor blades twirl. Engineering An 8-year-old girl sits on a deck and looks at some playhouse toys, such as a pink couch, and a pile of wood. Math A girl sits in a classroom looking ahead at the teacher.

Importance des représentations mentales initiales dans un processus d’apprentissage et expression libre Les documents du Nouvel Educateur n°196 Importance des représentations mentales initiales dans un processus d’apprentissage et expression libre Par Pierre Guérin « L'expérience vécue, la connaissance intellectuelle marquent leur empreinte sur notre appareil à percevoir le monde, au point d'en bouleverser le monde perçu. Notre représentation intellectuelle du monde peut nous gouverner jusqu'à nous rendre aveugle à tout ce qui n'est pas compris dans cette représentation. » Boris CYRULNIK Sommaire Avant‑propos ........................................................................................................ 1 Quelques exemples d'expression de représentations mentales initiales................... 2 La communication ................................................................................................. 5 Fonctionnement Codage Décodage Une composante biologique .................................................................................. 8 Comment s'édifie notre système de références

Colorful Convection Currents Fill two bottles with warm water from the tap and the other two bottles with cold water. Use food coloring or the Fizzers coloring tablets to color the warm water yellow and the cold water blue. Each bottle must be filled to the brim with water. Hot over cold: Place the index card or old playing card over the mouth of one of the warm water bottles. If you are using our Split Demo Tank, follow these directions: Make sure that the tank divider is firmly in place. Hot air balloons rise because warm air is lighter than cold air. The movement of warm and cold water inside the bottles (or tank) is referred to as the convection current. Although the bottles whose colored liquids mix are more interesting to watch, the other set of warm and cold water bottles helps to illustrate another important phenomenon that occurs in the atmosphere during the winter months. What are the results of temperature inversion? More Weather Experiments

Teaching with TLC: 10 ways to make physical science FUN! This month we've been completing lots of physical science lessons that my kids do not want to put down. I just love it when they are hooked on learning! My kids have been learning all about simple machines, matter, and electricity from the best science teachers at the Edison Home. What better place to learn about science than Edison's home! As you may already know, I REALLY like hands-on learning because those are the lessons that make learning stick. We watched Bill Nye, The Science Guy teach about Atoms in this great video! The kids used cereal to model the different spacing of atoms in matter. We made a 3-D atom using an orange, candy, and toothpicks. Here my boys are watching the video that is mentioned above. The teacher in the video had them make negatively charged and positively charged atoms. I was on a quest to make an edible atom. When we were creating the atom, one of my sons exclaimed, "Oh, now I get it! I can't believe how much learning took place during this lesson.

Conceptions sur la gravité - WikiPistes Un article de WikiPistes. Article 1 - A cross-cultural investigation of children’s conceptions about the earth, the sun and the moon: Greek and American data Cette recherche portant sur les conceptions initiales des enfants sur la loi de la gravité s’est déroulé simultanément avec 60 enfants américains et 90 enfants grecs afin d’observer les conceptions initiales universelles des enfants. Le groupe d’enfants américains étaient constitué de 20 enfants de première année (âgés de 6 ans), 20 enfants de troisième année (âgés de 9 ans) et 20 enfants de cinquième année (âgés de 11 ans) provenant tous de la classe socio-économique moyenne et fréquentant une école primaire située dans la région ouest des États-Unis. Les résultats de recherche ont été recueillis à partir d’un questionnaire présenté aux enfants. Article 2 - Unraveling student’s misconceptions about the earth’s shape and gravity Sources Cary, I.

Chemical Reaction Games For Kids & Learning About Combustion In a chemical reaction a reactant is consumed during a reaction while a product is formed as a result. In this game two examples of chemical reactions are highlighted: combustion and gasification. In both cases a hydrocarbon (such as oil, coal or wood) and oxygen are the reactants, while the products vary depending on the process and amount of oxygen. Any product of a chemical reaction that is not the intended product of the reaction is a by-product. In combustion processes, heat is the main intended product, and the chemical compounds that are produced are considered by-products. There are two types of combustion: complete and incomplete. Gasification converts hydrocarbons by reacting them at high temperatures with a controlled amount of oxygen and steam.

Physicists Achieve Quantum Teleportation of Photon Over 25 Kilometers For the first time, a team of physicists have successfully teleported a quantum state of a photon to a crystal over 25 kilometers away through a fiber optic cable. This effectively showed that the photon’s quantum state, not its composition, is important to the teleportation process. The team was led by Nicolas Gisin of the University of Geneva and the results were published in the journal Nature Photonics. With this new paper, Gisin’s team has successfully squashed the previous record they set a decade ago by teleporting a quantum state of a proton 6 kilometers. The quantum state of the photon is able to preserve information under extreme conditions, including the difference between traveling as light or becoming stored in the crystal like matter. To test this and ensure what they were observing was actually happening, one photon was stored in a crystal while the other was sent along optical fiber, over a distance of 25 kilometers.

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