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HEAT TRANSFER Rise As They Heat up and Fall As They Cool, Creating Circular Convection Currents

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HEAT TRANSFER ������� �� ������� �������� ���� ������ Rise As They Heat up and Fall As They Cool, Creating Circular Convection Currents SNOWMAN STORY How Heat Moves RESEARCH FILE RESOURCE A instance, when you hold an ice cube, heat is transferred from your warm hand to the cold ice and Conduction is the transfer of heat through solids. Some substances, such as copper and iron, are better conductors than others, such as wood and paper. Convection is the transfer of heat by the movement of currents HEAT TRANSFER rise as they heat up and fall as they cool, creating circular convection currents. Radiation is the transfer of energy by electromagnetic waves. When electromagnetic waves come in contact with an object, they transfer heat to that object. Source: Center for Science Education, EDC SNOWMAN STORY After the Race RESEARCH FILE RESOURCE B 1 Keep Moving 2 Hydrate drink enough, you could end up in the medical tent due to dehydration. 3 Stay Warm ket. These thin sheets of silvery foil provide lightweight insulation, slowing the loss of heat from your body. wind rain body heat back your body heat, creating a layer of warm air around you. The plastic outer surface protects you from elements like wind and rain that remove heat from your body. Source: Center for Science Education, EDC SNOWMAN STORY Pop Quiz RESEARCH FILE RESOURCE C 1. How high can a popcorn kernel fly when it pops? 2. How much larger is a popped kernel than an unpopped one? 3. How big was the biggest popcorn ball ever made? How much popcorn do Americans eat every year? theaters comes from the sale of popcorn and other snacks. How many ways are there to cook popcorn? three methods are examples of the three different types of heat transfer. When you pop corn on your stovetop, the pot conducts heat from the burner wave energy. What’s the best way of making popcorn? Each method has its pros and cons. Cooking in a microwave is easy—just set the timer and press start. But microwave popcorn often contains a lot of fat. popcorn is cheap—bags of kernels cost less than packets of microwave popcorn. And you can use your favorite seasonings to make it taste just right. Source: Center for Science Education, EDC SNOWMAN STORY How To Move Pet Fish RESEARCH FILE RESOURCE D So how do you make sure your fish survive the Styrofoam cooler. 1 the water in the traveling container clean. 2 wet during the trip. 3 of oxygen during the trip. 4 Carefully move the fish from the tank to the bag. Tie off the top of the bag, leaving as much air as possible in it so it puffs up like balloon. Close the cooler lid to insulate the container completely. 5 the move. temperature. The foam contains many tiny air bubbles, and those air arrive at their new home safe and sound. Source: Center for Science Education, EDC SNOWMAN STORY The Thermos Bottle RESEARCH FILE RESOURCE E chocolate, and your cocoa will still be steaming hot hours later. out from the space between its walls, creating a vacuum. The flask walls have a reflective, silvery surface. The combination of the vacuum and the reflective walls greatly reduces the flow of heat into or out of the flask. Here’s why the vacuum flask is such a good insulator: 1 Conduction cap vacuum. 2 Convection air (or any other fluid) in a vacuum. outer case 3 Radiation (electromagnetic waves) can travel glass flask through a vacuum. But electromagnetic greatly reducing heat transfer by radiation. reflective walls vacuum Source: Center for Science Education, EDC.
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