NAME PERIOD UNIT 1 - FORCE TEMPERATURE IN THERMAL SYSTEMS ACTIVITY LESSON DESCRIPTION SCORE/POINTS 1. TX PP. 64-76 /46 2. WS READING GUIDE CONCEPT APPLICATION /21 3. MS MATH PRACTICE (Heat formula) /20 4. MS MATH WORKSHEET (Celsius & Fahrenheit) /15 5. WS PEVIOUS UNITS REVIEW /11 Objectives: Explain the difference between Thermal Energy, Heat, and Temperature Explain the difference between calorie, BTU, and specific heat Define conduction, convection, and radiation and give examples where each type of heat transfer is found Explain the difference between Latent Heat and Sensible Heat. Graph temperature changes and phase changes and label latent heat and sensible heat. Solve problems using the equation H = mc ΔT Convert between Celsius and Fahrenheit List the freezing and boiling points of water on the Celsius and Fahrenheit scales.
WORKSHEET PP. 64-76 1. The property that enables a body to do work is called (1) 2. Energy of motion is called (1) 3. What determines whether an object exists in the solid, liquid, gas, or plasma state? (1) 4. What is thermal motion? (1) 5. What is thermal energy? (1) 6. Whenever two bodies are brought together, thermal energy flows how? (1) 7. The hotness of a body is a property called (1) 8. Temperature is determined by what? (1) 9. What is the difference between thermal energy and temperature? (1) 10. Explain why a pot of boiling water has a higher temperature than a frozen lake, but the frozen lake has more thermal energy. (2) 11. Most materials when their temperature increases and when temperature decreases. (2) 12. Explain how a thermometer works. (1) 13. What is the freezing and boiling points on a Celsius scale? (2) 14. What is the freezing and boiling points on a Fahrenheit scale? (2) 15. Explain the process of heat conduction. (1) 16. What is heat? (1) 17. Heat never flows from what? (1) 18. Heat is in transit. (1) 19. Heat flow depends on a difference, but not necessarily a difference. (2) 20. What is the prime mover in thermal systems? (1)
21. has a much higher capacity for storing thermal energy than almost every other substance. (1) 22. 1 calorie = Joules (1) 23. Define calorie: (1) 24. Define Btu: (1) 25. Define Specific heat: (1) 26. List the specific heat for the following substances. (6) Label your answers Water Air Aluminum Iron Brass Lead 27. Write the formula for the Heat transferred to an object, and tell what each letter means. (5) 28. Substance change state at (1) 29. What is the definition of melting point? (1) 30. What is the definition of boiling point? (1) 31. What is heat of fusion? (1) 32. What is heat of vaporization? (1)
CONCEPT APPLICATION (15 points) 1. A thermometer that shows both Celsius and Fahrenheit is placed in a glass of ice water. After the temperature reaches thermal equilibrium what will the temperature read on that thermometer in Celsius? and in Fahrenheit? (2pts) 2. A thermometer that shows both Celsius and Fahrenheit is placed in a pot of boiling water. After the temperature reaches thermal equilibrium what will the temperature read on that thermometer in Celsius? and in Fahrenheit? (2pts) 3. When wax melts is heat absorbed by the wax or released? (1pt) 4. When wax freezes - is heat absorbed by the wax or released? (1pt) 5. Explain the difference between thermal energy and heat. (2 pts) 6. Explain the difference between temperature and heat. (2 pts) 7. When you place ice in a glass of water, the ice melts and the temperature of the water goes down. Does cold flow out of the ice, or does heat from the water flow into the ice? (1 pt) 8. A thermometer at room temperature is place in a glass of cold water. a) After the thermometer and the water come to thermal equilibrium, how do their temperatures compare? (1pt) b) Does heat flow into the thermometer or out of the thermometer when it is placed into the colder water? (1pt) c) Does heat flow into the water, or out of the water? (1pt) d) If you only had a few drops of cold water, why would it be impossible to put a room temperature thermometer in it and get an accurate reading of the starting temperature of the water? (1pt) 9. Define Conduction and give an example of heat transfer with conduction. (2 pts) 10. Define Convection and give an example of heat transfer with convection (2 pts) 11. Define Radiation and give and example of heat transfer with radiation (2 pts)
MATH PRACTICE Heat Use the formula H = mc ΔT to solve the following problems. On each problem, write the correct formula (1pt), put the numbers in the formula (1pt), write the answer (1pt), label the answer (1pt). Mass Specific heat Temp. difference 1. A piece of copper with a mass of 150 grams is heated from 25 degrees Celsius to 45 degrees Celsius. The specific heat of copper is 0.093 cal/gmc. Find the heat gained by the copper. 2. A cup of water with a mass of 150 grams is heated from 25 degrees Celsius to 45 degrees Celsius. The specific heat of water is 1.00 cal/gmc. Find the heat gained by the water. 3. A 70 gram piece of aluminum is cooled in a cup of water. It cools from 85 degrees Celsius to 35 degrees Celsius. The heat lost by the aluminum is 770 calories. What is the specific heat of the aluminum? 4. A 200 gram piece of brass is cooled in some water. The specific heat of brass is 0.091 cal/gmc. The water gains heat of 819 calories. How much did the brass change temperature? 5. A 300 gram piece of glass is heated from 15 degrees Celsius to 80 degrees Celsius. The specific heat of glass is 0.021 cal/gmc. How much heat energy was required?
CHANGING BETWEEN CELSIUS AND FAHRENHEIT Using CADS & FAMS Method To Find o C A D S A = Add M = Multiply o F A M S S = Subtract D = Divide 40 1.8 40 To find o F : take the o C Add 40 = Multiply by 1.8 = Subtract 40= You have to press = between each operation so the calculator works correctly. Example: 0 o C + 40 = 40 x 1.8 = 72-40 = 32 o F For each problem, you must show your work like the example above, and label your answer. (3 points each: work, answer, label) 1. A thermostat on an automobile engine is calibrated to open and allow engine fluid to circulate through the radiator when the fluid temperature reaches 180 o F. What is this temperature on the Celsius scale? 2. The temperature of a hot summer day, in a non-air-conditioned shop reaches 36.7 o C. What is this temperature equal to on the Fahrenheit scale? 3. A 5W motor oil does not become too thick even at temperatures as low as 5 o F. What is this temperature equal to in degrees in Celsius? 4. A thermocouple measures the temperature of molten aluminum at a temperature of 649 o C. What would this be on in Fahrenheit? 5. A nurse at a hospital emergency room tells Mrs. Nakamura that her baby has a temperature of 103 o F. Mrs. Nakamura is a visitor from Japan and only understands the meaning of temperature in degrees Celsius. What is her baby s temperature in degrees Celsius.
Previous Unit Review The amount of heat energy that radiates out from a hot object also follows the inverse square law (just like gravity and charge). You divide by the distance squared 1. So pretend you are sitting around a camp fire. If someone puts more wood on the fire so it is 2 times bigger how much more heat would you feel? (1pt) 2. If you move 2 times farther away from the fire, how much heat energy do you feel? (remember: distance squared) (1pt) 3. What if you move 3 times farther from the fire, how much heat energy do you feel? (1pt) 4. If a charged objects are moved 2 times closer together, how will the electrical force between them be affected? (1pt) 5. Which way will the ball in the diagram move? (Assume the distance between sides is the same) (1pt) -1-5 +2 6. Which way will the ball in the diagram move? (Assume the distance between sides is the same) (1pt) -1-3 -1
7. Suppose an object on the Earth weighs 1200 N. If it is moved up a ladder the same height as radius of earth. (so now it is 2 times farther from the center) how much would it weigh? (1pt) 1200 N?_Newtons 1 radius 2 radii Use this picture for the next 3 questions. B. Force = 800 N A Force = 600 N C. Force = 400 N D. Force = 400 N. E. Force = 300 N 8. Which forces are balanced? (1pt) 9. Which forces are unbalanced? (1pt) 10. What is the magnitude (amount) and direction of the net force on the object? (2pts)