5.1, Building a thermometer

Transcription

1 5.1, Building a thermometer 1) Draw Room Temperature Line (See R on diagram) 2) Draw water line and record temperature after thermometer has been in cold bath for 5 minutes. Record cold temp. = ºC 3) Draw water line and record temp after thermometer has been in hot bath for 3 minutes. Record hot temp. = ºC 4) Measure distance between cold line and hot line (in cm). Calibration distance = cm. 5) Calibrate thermometer. Temperature difference (hot cold) divided by measured distance between cold and hot lines. ( 1 cm = ºC) 6) Use your thermometer to determine room temperature. (Tc)ºC + (D C-R )cm x (Calibration)ºC/cm Room Temp = ºC H R C

2 5.1, Calibrating a Thermometer Example 1; T C = 5ºC, T H = 85ºC, Measured distance between lines H and C = 19 cm The calibration = (T H T C ) (distance between T H and T C ) (85ºC 5ºC) (19cm) = 80ºC 19 cm = 4.2ºC/cm Distance from T C to T R = 5 cm Temp of the room is therefore is 5cm x 4.2 C/cm = 21 C Oops not 21ºC, actually its: 21ºC + 5ºC = 26ºC H C

3 GROUP QUIZ Just do the first page today you will finish the quiz on Thursday.

4 GROUP QUIZ Just do the first page today you will finish the quiz on Thursday. Determine Group Roles: FACILITATOR makes sure everyone participates RECORDER records group answers on their sheet. Put their name first and then the rest of the group TIME KEEPER makes sure to keep the group on task MONITOR watches to make sure other group members are fulfilling their roles GROUPS 2 and 8 work in the back Groups 3 and 7 use chairs from groups 2 and 8 to face each other!

5 17) CONDUCTION: The transfer of energy in the form of heat (or electricity) from one atom to another within an object by direct contact. Occurs in solids, liquids, and gases.

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7 Name Heat Transfer Across 6 Hot air (or water) rises because it becomes less than the surrounding fluid. (5) 7 Heat transfer between two solid objects that are in contact with each other is. (10) 8 Convection currents may be observed when water is heated past its. (7,5) 9 The sun warms the Earth through the type of heat transfer called. (9) 11 The atoms in all are constantly moving. (6) 12 is the measure of all kinetic energy in a sample of a material. The more kinetic energy there is, the higher this is. (11) 14 The warming of the Earth's surface occurs mostly through radiation from the. (3) Down 1 A convection is formed when warm fluid rises and cold fluid sinks. (7) 2 The flow of energy from an object with a higher temperature to a lower temperature object will continue until both objects have reached thermal (they are both the same temperature). (11) 3 The energy of movement is energy. (7) 4 In heat transfer by radiation, the heat energy is transferred through space by waves. (15) 5 Adding layers of slows the rate of heat transfer, as when people wear several layers of clothes on a cold day. (10) 10 is heat transfer between locations by the movement of fluids (liquids or gases). For example, a floor heater will warm a room because hot air rises. (10) 12 Heat occurs through conduction, convection, and radiation. (8) 13 Warmer fluid, cools, and then sinks, forming convection currents. (5)

8 Name Heat Transfer A couple of helpful words: Equilibrium Insulation 13 Electromagnetic 14 Across 6 Hot air (or water) rises because it becomes less than the surrounding fluid. (5) 7 Heat transfer between two solid objects that are in contact with each other is. (10) 8 Convection currents may be observed when water is heated past its. (7,5) 9 The sun warms the Earth through the type of heat transfer called. (9) 11 The atoms in all are constantly moving. (6) 12 is the measure of all kinetic energy in a sample of a material. The more kinetic energy there is, the higher this is. (11) 14 The warming of the Earth's surface occurs mostly through radiation from the. (3) Down 1 A convection is formed when warm fluid rises and cold fluid sinks. (7) 2 The flow of energy from an object with a higher temperature to a lower temperature object will continue until both objects have reached thermal (they are both the same temperature). (11) 3 The energy of movement is energy. (7) 4 In heat transfer by radiation, the heat energy is transferred through space by waves. (15) 5 Adding layers of slows the rate of heat transfer, as when people wear several layers of clothes on a cold day. (10) 10 is heat transfer between locations by the movement of fluids (liquids or gases). For example, a floor heater will warm a room because hot air rises. (10) 12 Heat occurs through conduction, convection, and radiation. (8) 13 Warmer fluid, cools, and then sinks, forming convection currents. (5)

9 CHECK YOUR ANSWERS!

10 PLANET EARTH II LIST: 5 to 10 bullet statements of something interesting or something you learned on the back side of the crossword puzzle.

11 18) Pants were hung on a clothesline overnight and the temperature dropped below freezing explain what happened: The water in the damp pants lost heat to the environment and changed phases from liquid to solid.

12 REMEMBER, heat always travels from warmer to cooler areas! 1) Heat went from punch to freezer. Punch lost enough heat to change states from liquid to solid 2) The heat from the teakettle caused the water particles to expand and become gas particles

13 19) Kinetic Energy and the flask 3) Air and water particles escape Plastic tubing 2) KE inside flask increases Flask Little bit of water (keeps the temperature at or below 100 C) 1) add heat

14 Hints: At first air pressure (frequency of particle collisions with flask) inside and outside flask are equal. But as particles inside flask cool and lose KE, air pressure inside becomes lower than outside. Air Pressure Heat source gone, flask cools, air inside cools as particles lose KE

15 Example 2 Distance between the hot and cold lines is 6 centimeters. Distance between cold and unknown lines is 1 centimeter. T hot = 70 C T unknown = T cold = 10 C (70-10)ºC 6cm = 60ºC/6cm = 10ºC/cm 10ºC/cm x 1cm = 10ºC 10ºC + 10ºC = 20ºC

16 Example 3 Distance between the hot and cold lines is 4 centimeters. Distance between cold and unknown lines is 2 centimeter. T hot = 80 C T unknown = T cold = 20 C (80-20)ºC 4cm = 60ºC/4cm =15ºC/cm 15ºC/cm x 2 cm = 30ºC 30ºC + 20ºC = 50ºC

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18 Building a Thermometer 1. Temp Cold (T C ) C 2. Temp Hot (T H ) C 3. Distance from T C to T H 4. Calibrate thermometer 5. Distance from T C to T R What is the room temp.? Temperature of Room = (Tc)ºC + (D C-R )cm x (Calibration)ºC/cm (Calibration)ºC/cm = (T H T C )ºC (D H-C )cm H R C

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