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Conduct a simple experiment with copper and plastic beads to understand why metal and plastics feel different when touched. Compare temperatures, discuss conductivity, and analyze thermodynamic concepts.
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Heat Activities OP Created for OP Physics By Dick Heckathorn 16 February 2K+4
WHY DO PLASTIC AND METAL FEEL DIFFERENT? 3D2 page 68
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • Materials: • 2 Styrofoam cups • small copper beads • small plastic beads • thermometer
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 1 . Fill one cup about halt full of small copper beads and the other with the same amount of plastic beads.
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 2. Put your finger in each of the cups. • Which material feels warmer to the touch?
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 3. Have your partner feel each material also. Do you agree about which material felt warmer?
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 4. Using a thermometer, MEASURE and RECORD the temperature of the copper and plastic beads. • Temperature of Copper = ___ Temperature of Plastic = ___ • 5. EXPLAIN your observations.
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 6. If you were to put the copper and the plastic in the refrigerator, what would you PREDICT about the way they would feel if you were to do the same experiment again? • Why do you predict this?
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 7. Obtain some plastic beads and some copper beads that have been in a cool place. Which material feels colder to your fingers?
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 8. MEASURE and RECORD the temperature of the beads. • Temperature of Copper = ___ • Temperature of Plastic = ___
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 9. Would you expect a good conductor to feel warmer or colder if you were to touch it after it had been outside all during a winter night?
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 10. Do you think that your clothing is a good conductor or a poor conductor? • EXPLAIN why.
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 11. Would you expect carpet or tile flooring to feel colder when you step on it in the morning? • EXPLAIN why.
WHY DO PLASTIC AND METAL FEEL DIFFERENT? • 12. When you go home today, compare as many objects as you can that are the same temperature. • Which objects felt warmest? • Which objects felt coldest? • How will you know that these objects were at the same temperature?
WHAT HAPPENS TO TEMPERATURE WHEN WATER CHANGES STATE? 1C2 page 15
WHAT HAPPENS TO TEMPERATURE WHEN WATER CHANGES STATE? • Materials: • hot plate • beaker • crushed ice • thermometer • stirring rod • graph paper
WHAT HAPPENS TO TEMPERATURE WHEN WATER CHANGES STATE? • 1. Fill the beaker half full of crushed ice. MEASURE and RECORD the temperature of the ice.
WHAT HAPPENS TO TEMPERATURE WHEN WATER CHANGES STATE? • 2a. Place the beaker on the hot plate and begin warming the ice. MEASURE and RECORD the temperature at 1 ‑minute intervals.
WHAT HAPPENS TO TEMPERATURE WHEN WATER CHANGES STATE? • 2b. Keep the thermometer tip off of the bottom of the beaker. Stir continuously as measurements are made.
WHAT HAPPENS TO TEMPERATURE WHEN WATER CHANGES STATE? • 2c. Continue to take measurements until you have RECORDED at least 3 measurements after the water is boiling.
WHAT HAPPENS TO TEMPERATURE WHEN WATER CHANGES STATE? Min oC Min oC Min oC
WHAT HAPPENS TO TEMPERATURE WHEN WATER CHANGES STATE? • 3. GRAPH your results. • 4. Did the temperature rise evenly during the total time of heating? EXPLAIN.
TEMPERATURE AND SOME EFFECTS OF HEAT 2A3F page 25
TEMPERATURE AND SOME EFFECTS OF HEAT • 1. What is the composition of matter? • Did you say atoms and molecules?
TEMPERATURE AND SOME EFFECTS OF HEAT • 2. In solids, what do the atoms or molecules do? • In a liquid? • In a gas?
TEMPERATURE AND SOME EFFECTS OF HEAT • 3. How do we measure how fast the motion of the atoms or molecules? • Did you say temperature?
TEMPERATURE AND SOME EFFECTS OF HEAT • 4. Thus, how do we change the temperature of a substance? • Add heat energy.
TEMPERATURE AND SOME EFFECTS OF HEAT • 5. Last time we heated a ball that would go through a ring. • What happened when we heated the ball? • It expanded and did not go through the ring.
TEMPERATURE AND SOME EFFECTS OF HEAT • 6. How does one explain the metal ball expanding and not through the ring? • The particles vibrated faster and in so doing occupied more space.
TEMPERATURE AND SOME EFFECTS OF HEAT • 7. Last time we saw foam balls in a wire cage. • What happened when a fan was aimed to hit the balls? • The faster the fan was turning, the further the balls spread out.
TEMPERATURE AND SOME EFFECTS OF HEAT • 8. This is exactly what happens when the particles in the metal ball was heated.
TEMPERATURE AND SOME EFFECTS OF HEAT • 9. What was considered a possible cause for the electrical outage last summer? • Sagging electrical wires due to….
TEMPERATURE AND SOME EFFECTS OF HEAT • 10. What happened to the size of the foam balls as they moved faster? • The size did not change.
TEMPERATURE AND SOME EFFECTS OF HEAT • 11. The model we have just described is called the “Kinetic” model. • “Kinetic” refers to things that are in motion.
TEMPERATURE AND SOME EFFECTS OF HEAT • 12 This model explains why ‘almost’ all solids, liquids and gasses expand when heated and contract when cooled.
HOW CAN A THERMOMETER BE CALIBRATED? 2D2 page 36
HOW CAN A THERMOMETER BE CALIBRATED? • Materials: • unmarked thermometer • crayon or wax marker • index card • water‑resistant tape • boiling water • ice water mixture
HOW CAN A THERMOMETER BE CALIBRATED? • 1 . Design a method by which you could mark off your thermometer into units which could be used to measure the temperature of common objects.
HOW CAN A THERMOMETER BE CALIBRATED? • 2. Your method today: • a. Place your thermometer in a container that contains ice water. • b. Mark the location of the red liquid on your thermometer.
HOW CAN A THERMOMETER BE CALIBRATED? • c. Place your thermometer in a container of boiling water. • d. Mark the location of the red liquid on your thermometer.
HOW CAN A THERMOMETER BE CALIBRATED? • 3. To test your calibration: • a. Place your thermometer in a third container – with water. • b. Write down the temperature of the water according to your thermometer.
HOW CAN A THERMOMETER BE CALIBRATED? • c. Measure the temperature of this water using a calibrated thermometer. • d. How do the two readings compare?
HOW CAN A THERMOMETER BE CALIBRATED? • e. How well did you calibrate your thermometer? • f. How well did the temperature of the water compare to others that measured the same water?
HOW MUCH HEAT ENERGY DOES IT TAKE TO MELT AN ICE CUBE? 3B4 page 58
HOW MUCH HEAT ENERGY DOES IT TAKE TO MELT AN ICE CUBE? • Materials: • Styrofoam cup • thermometer • graduated cylinder or measuring cup • ice water • warm water • ice cubes • graph paper
HOW MUCH HEAT ENERGY DOES IT TAKE TO MELT AN ICE CUBE? • 1. PREDICT what the final temperature would be if you were to mix 1 measure of warm water with 1 measure of ice cold water 0oC but with no ice cubes).
HOW MUCH HEAT ENERGY DOES IT TAKE TO MELT AN ICE CUBE? • 2. Pour some water that has been cooled to the temperature of ice water into a styrofoam cup
HOW MUCH HEAT ENERGY DOES IT TAKE TO MELT AN ICE CUBE? • b. Fill your graduated cylinder with the same volume of warm water. • c. Measure and record the volume (in ml) and its temperature (in oC).
HOW MUCH HEAT ENERGY DOES IT TAKE TO MELT AN ICE CUBE? • d. Pour the warm water into the styrofoam cup with the ice water. • e. Stir the two mixtures together. • f. Measure and record the temperature of the mixture.
HOW MUCH HEAT ENERGY DOES IT TAKE TO MELT AN ICE CUBE? • e. How close were you to your prediction? • oC • ___ Predicted temperature ___ Temperature of ice water • ___ Temperature of mixture