Getting Colder Quicker: Newton’s Law of Cooling In Action! Overview (Days 1-3) Grade Level: Duration: 11th – 12th 3 x 50 min periods Subject: Calculus: Applications of Rates of Change/Derivative Prepared By: Mike Borowczak Materials Needed Minimum reqs. Thermometer & Watch; See individual days for full listing with optional equip. Analyze Learners Overview & Purpose (STEMcinnati theme): Students will learn about Newton’s Law of (Heating and) Cooling, specifically they will learn about real world applications of Newton’s Law of Cooling. By learning about one specific application of rates of change (Newton’s Heating & Cooling Law) students will be able to understand how “rates of change” (derivatives) play a part in their daily lives. Applications: Cooling of Nuclear Reactors down to the cooling of an Integrated Chip in a Cell Phone. Maintaining warmth from buildings to your favorite winter beverage. Careers: Materials & Chemical Engineering, Mechanical Engineering, Civil and Environmental Engineering, Electrical Engineering, Physicist, Chemist, Biologist, Forensic Pathologists (See Appendix A) Society: Keeping us safe from Nuclear Disaster, down to allowing our everyday technology to exist without exploding. Science: Heat Transfer between two materials of different temperature Technology: Use of temperature probes, calculators, and computers 1 to collect and visualize data. Engineering: Creating containers and casings that allow rapid/slow heat transfer to their environment. Mathematics: Computation of Slopes at various points to derive non-trivial derivative; taking the derivative of given functions; primer for the concept of differential equations. 1 Education Standards Addressed Ohio Benchmarks 11th/12th Grade: Measurement D: Solve problem situations involving derived measurements Patterns, Functions and Algebra A. Analyze functions by investigating rates of change, intercepts, zeros, asymptotes, and local and global behavior. Data Analysis and Probability A. Create and analyze tabular and graphical displays of data using appropriate tools, including spreadsheets and graphing calculators. B. Use descriptive statistics to analyze and summarize data, including measures of center, dispersion, correlation and variability. C. Design and perform a statistical experiment, simulation or study; collect and interpret data; and use descriptive statistics to communicate and support predictions and conclusions. Scientific Inquiry & Scientific Ways of Knowing A for both. Lesson can be adapted for use provided access to: thermometer and watch Select Goals and Objectives Goals and Objectives (Specify skills/information that will be learned.) Teacher Guide Goals: Students will understand the fundamentals of Newton’s Law of Cooling, giving them the insight to understand the importance of the derivative (rates of change) in their everyday life. Objectives: 1. Students will be able to recognize the how the temperature of an object changes over time (during cooling). 2. Students will analyze how changing an object’s material composition or Size affects the “rate of change” of heat transfer. 3. Students will be able to explain some of the factors involved in designing a container to have specific heat transfer characteristics. 4. Students will be able to approximate the derivative of an unknown/non-trivial function. Student Guide While this lesson is geared towards students in an Introductory High School calculus class with a strong grasp of pre-calculus, this lesson can be adapted to any level which has fundamental knowledge of slopes (High School Geometry). The ultimate goal is for students to grasp that things that change over time have measurable “Rates of Change.” Assessment Getting Colder Quicker! Day One Materials Needed Thermometer, Watch, Ruler, Containers (See Attached), and Hot H 2O (Sig. Above Room Temp 80 ºC+); Optional/Recommended: TI:84+ (or better), CBL Temperature Probe Analyze Learners Overview & Purpose (STEMcinnati theme): Day One covers all four STEM areas! Select Goals and Objectives Teacher Guide Goals and Objectives Goals: 1. Students will be able to recognize the how the temperature of an object changes over time (during cooling). 2. Students will analyze how changing an object’s material composition or Size affects the “rate of change” of heat transfer. 4. Students will be able to approximate the derivative of an unknown/non-trivial function. (Specify skills/information that will be learned.) Education Standards Addressed See Overview Student Guide Use pre-assessment to address major misconceptions: e.g. temperature of a liquid can not drop below room temp (given no change in pressure etc). Also use pre-assessment to determine biggest area of concern e.g graphing the derivative Objectives: Focus on Main Objectives 1,2, & 4 Select Instructional Strategies – Information (Catch, give and/or demonstrate necessary information, misconceptions, etc…) Utilize Technology 1. Pre-assessment (10 minutes) 2. Catch (10 minutes) a. Teacher will place the same temperature liquid (hot water) in two similar containers (e.g. two different ceramic mugs) – students will touch the exterior and experience and deduce that different objects transfer heat differently. Note: You may want to look for videos online showing rapid heat transfer and its effects (e.g. rapid heating / cooling of glass & ceramics) Use of data collection tools Basic thermometer & watch CBL system Assessment During this time students will be introduced to the idea of heat transfer and exposed to the wide breadth of possible applications of the derivative. See Assessment Questions Document (GCQ_assess.[docx|pdf]) Other Resources Require Learner Participation Activity (Describe the independent activity to reinforce this lesson) Evaluate (Assessment) (Steps to check for student understanding) – See Objectives above Inquiry based activity (50 minutes) Use Cool_it_down_lab.[docx|pdf] as Guide 1. Quickly Review Procedure w/Students [2 minutes] 2. Create groups for each Container Material Type & Allow students to get materials & setup [3 minutes] 3. Students will now measure the temperature of each of their 3 containers once every 30 seconds to 1 minute a. Optional Section So that students understand the difficulties in real world data collections students will collect data round-robin For each data point a new student will measure the temperature and will not share their measurement with the others 4. While student are measuring others are plotting and computing the slope of the tangent line at several points for each of the containers Through observation the students should see the cooling curve (an exponential decay) Reflect & Assess (5-10 minutes) 1. Bring Students back and ask them what they have observed a. How do they think what they’ve done happens in “the real world” 2. Ask students to plot the tangent line slopes for homework (finish computing them) In the reflection phase students will confirm the relationship, and will begin understanding objective 4 (approximation of the derivative) Students should also see that size matters – in particular volume/surface area. + The lower the number the faster the heat transfer occurs Students will calculate the rate of change by hand At this point the students will not see the difference between different material types Students will also not yet realize the importance of effective data collection Additional Notes Getting Colder Quicker! Day Two (Optional – Replace with Discussion of Homework) Materials Needed Computing Resource, Excel or OpenOffice (free!) Analyze Learners Overview & Purpose (STEMcinnati theme): Education Standards Addressed See Overview In Class: Use of Technology and Mathematics prevail in use of Excel & Calculus Homework: Science and Engineering to develop the idea for their aparatus Select Goals and Objectives Goals and Objectives (Specify skills/information that will be learned.) Select Instructional Strategies – Information Teacher Guide Assessment Goals: Be able to plot data and observe overall difference between various characteristics. Objectives: 1. Students will analyze how changing an object’s material composition or Size affects the “rate of change” of heat transfer. Ask students how accurate they think their measurements are – how would they represent it and model it. Point out how (Catch, give and/or demonstrate necessary information, misconceptions, etc…) Utilize Technology Student Guide Computing Resource, Excel or OpenOffice (free!) Students will see why it’s important to clearly represent the data that has been collected. Other Resources Require Learner Participation Activity (Describe the independent activity to reinforce this lesson) Evaluate (Assessment) (Steps to check for student understanding) – See Objectives above Taking the data collected the previous day students will input and plot the following: 1. The combined group data for each container with trend lines & Equations 2. Optional: Individual data and trend lines + equations Students will then present their findings to the class in a 1 minute “blurb.” Students will have first hand experience using excel a tool for rapid plotting and evaluation of data. Reflect & Assess (5-10 minutes) 1. Bring Students back and ask them what they have observed a. Were they able to see the same graphs they plotted the day before b. Comparing the graphs with each other what did they see when different materials were used? In this reflection phase students will now understand how to quickly plot and find trendlines for data sets They will also understand that different materials cool down differently – e.g. they have different “K” values in their exponent. Evaluation in reinforcing objectives 1, 2 & 4. Assignment of problem to solve: “Look around your house – find a container or set of containers that would help you cool a liquid down quickly” In reflection students will also realize the importance of complete and accurate measurement. Those measuring at 0 and 30sec will have much better approximations of the temperature/time graph than students measuring at 1:00 and 1:30. Additional Notes Getting Colder Quicker! Day Three Materials Needed Day 1 Materials + Student Brought Materials + Extra Teacher Provided Materials Analyze Learners Overview & Purpose (STEMcinnati theme): Education Standards Addressed See Overview Today is all about putting it all together – Engineer a complete solution based off a problem statement. Select Goals and Objectives Goals and Objectives (Specify skills/information that will be learned.) Teacher Guide Goals: Students will design and construct a container that will rapidly cool down a liquid to room temperature. Students will see several practical applications for Newton’s laws of cooling. Student Guide Assessment Students will see that they are capable of creating and designing a container which can rapidly release heat! Objectives: 1. Students will be able to explain some of the factors involved in designing a container to have specific heat transfer characteristics. 2. They will explain by actually designing a container to rapidly cool down a liquid. Select Instructional Strategies – Information (Catch, give and/or demonstrate necessary information, misconceptions, etc…) Utilize Technology Catch: Students are doing another experiment – they think they’re cooling down 1) the same liquid at 2) the same temperature. They’re not – they are swapping liquids and the temperature of their liquid is much hotter than on day 1 – surprise – redesign if needed. Same technology as Day 1 + any additional items students bring Students may need to rethink their design since the temperature is going to be much hotter now. They also need to use teamwork to quickly build their solution so there’s time to test. Other Resources Require Learner Participation Activity (Describe the independent activity to reinforce this lesson) Activity is open ended. Stipulations are listed in the assignment handout Design a Container/Apparatus to quickly cool 1 Cup (8 fl oz) of Water. Your final design must fit within a 1 cubic foot of space (e.g. width x height x length can not exceed 1 ft3) Students will complete against each other to build a container/apparatus capable of quickly cooling down a liquid. Any liquids in your design (besides water) they must be non-toxic and must be approved before hand by instructors. Students will have 10 minutes to construct their apparatus and then 8 fl oz of 100 C water will be placed within their device and a counter will be started – time will end when once their liquid reaches room temperature. Evaluate (Assessment) (Steps to check for student understanding) – See Objectives above Evaluate student ability to cool down a liquid faster than the liquid being place in a Styrofoam container. Students will experience friendly competition with their peers. See Assessment Questions Document (GCQ_assess.[docx|pdf]) Post Assessment Important Attachments: 1. Pre-Post Assessment 2. Worksheets 3. PowerPoint 4. Reflection after lesson Reflection: What worked well: Student’s enjoyed the ability to work together to investigate Newton’s law. Documents we’re laid out in a straightforward manner – easy to ”fill in the important details.” The clear separation of tasks also was a benefit as the students knew what they were doing and why - e.g. day 1/2 collect data, day 2/3 input collected data. Students knowledge was reinforced that the derivative was nothing more than the change in slope of the tangent line of the cooling curve – thus accomplishing our initial objective. What didn’t work as well: Students quickly became agitated measuring the liquid with such high frequency / long duration. Suggest that you remove a variable from the equation – e.g. groups work on a single container (either type of size), this way the group is measuring one object and they can switch on/off measurements. Additionally – students thought that entering data was monotonous – unsure how to remedy this aside from again making the students switch on/off entering data – much like in the data collection phase.