1. © KCL. WCED. PENTECH. 2002 Energy going places 1. The Conduction of energy can be compared to a line of people passing a series of balls from one to another along the line. The people would represent molecules and the balls would represent energy. If in a crowded room a few people (molecules) could push their way across the room whilst carrying a ball (energy), this would be like a Convection current. Radiation is like someone throwing a ball (the energy) from one person (the molecule) at one end of a room, to another person (another molecule), at the other end of the room. DRAW diagrams to illustrate the processes of conduction, convection and radiation.

2. © KCL. WCED. PENTECH. 2002 Energy going places From the illustrations above, 1. DESCRIBE what is happening. 2. EXPLAIN what is happening. watch thermometer copper rod flame 2.

3. © KCL. WCED. PENTECH. 2002 Energy going places From the illustrations above, 1. DESCRIBE what is happening. 2. EXPLAIN what is happening. watch beaker of clear water Potassium permanganate crystal flame purple stain 3.

4. © KCL. WCED. PENTECH. 2002 Energy going places From the illustrations above, 1. DESCRIBE what is happening. 2. EXPLAIN what is happening. soot blackened bulb to thermometer watch thermometer flame separation of 0.5m 4.

5. © KCL. WCED. PENTECH. 2002 Energy going places Lamp 5. The ends of the thermometers have been painted (1) silver (2) white (3) shiny black (4) matt black. 1 2 3 4 RECORD your observations DRAW a CONCULSION

6. © KCL. WCED. PENTECH. 2002 Energy going places 6. Lesley’s cube is filled with boiling water or boiling oil. The bulbs of the thermometers are coated in matt black paint Matt black surface White surface Silver surface Shiny black surface LOOK at the thermometers carefully. RECORD your observations. What do you CONCLUDE ? DECIDE what must you be sure of for this to be a fair test?

7. © KCL. WCED. PENTECH. 2002 Energy going places 6. Here is a table of values for how much energy, in Joules per second, or Watts, that can pass across opposite faces of a block of material that is 1m x 1m x 1m when the temperature difference is 1 Celsius degree. energy OUT area of 1m x 1m1m thickness MaterialEnergy in watts Silver Copper Iron Brick Rubber Air 418 000 385 000 80 000 1 000 200 30 DESCRIBE any patterns you may see in this table of data energy IN temperature difference Vacuum0.0 Foam rubber80

8. © KCL. WCED. PENTECH. 2002 Energy going places 7. insulating glass wall silver coating reduces radiation and absorbtion vacuum stops conduction foam insulating supports insulating screw cap stops convection Keeping HOT Use the diagram and your knowledge of conduction, convection and radiation to EXPLAIN how a vacuum flask can keep its contents hot. insulating glass wall

9. © KCL. WCED. PENTECH. 2002 Energy going places 8. insulating glass wall silver coating reduces radiation and absorbtion vacuum stops conduction foam insulating supports insulating screw cap stops convection Keeping COLD Use the diagram and your knowledge of conduction, convection and radiation to EXPLAIN how a vacuum flask can keep its contents cold. insulating glass wall