1、Kinetic and Potential Energy Lesson Plan 1Kinetic and Potential Energy (Lesson Plan) (An Introduction to the Physics of Motion through the use of Milk Carton Cars)Suggested Grade Level 8-10Standard Statements3.1.4 E Recognize change in natural and physical systems.3.2.4 C Recognize and use the eleme
2、nts of scientific inquiry to solve problems.3.4.4 B Know basic energy types, sources, and conversions.3.4.4 C Observe and describe different types of force and motion.3.6.4 C Know physical technologies of structural design, analysis and engineering, finance, production, marketing, research and desig
3、n.3.7.4 B Select appropriate instruments to study materials. Content ObjectivesStudents will know that1. Potential energy represents the amount of energy stored in an object due to its height above ground. 2. Kinetic energy is the energy associated with the movement of an object. 3. The potential en
4、ergy of an object is equal to the product of its mass, its height above the ground, and the acceleration due to gravity.4. The kinetic energy of an object is equal to the product of its mass, the square of its velocity, and a factor of . 5. The potential energy of an object increases as its mass inc
5、reases and as its height above ground increases.6. The kinetic energy of an object increases as its mass increases and as its velocity increases.7. The acceleration of an object along a ramp is equal to the acceleration due to gravity multiplied by the ratio of the ramp, where the ratio of the ramp
6、is equal to the ramp height divided by the length of the ramp.8. The final velocity of an object can be calculated given its initial velocity, its acceleration over the distance of interest, and the time it took the object to traverse that distance. Process ObjectivesStudents will be able to1. Calcu
7、late the acceleration of a milk carton car along a ramp given the height and length of the ramp.2. Calculate the final velocity of a milk carton car at the bottom of a ramp given that it started from rest.3. Calculate the potential energy of a milk carton car at the top of a ramp given the ramp heig
8、ht and the total mass of the milk carton car.4. Calculate the kinetic energy of a milk carton car at the bottom of a ramp given the total mass of the car and its final velocity at the bottom of the ramp.5. Calculate an average time and average distance given three times and three distances.Assessmen
9、t Strategies1. Evaluation of completed student handouts.2. Group discussion of the questions in Part 4.Kinetic and Potential Energy Lesson Plan 2MaterialsPer group: 1 milk carton (8-oz. or larger) 2 axles 4 in. long; 3/8 in. diameter plastic or wooden dowel rod 1 drinking straw cut in half (each hal
10、f approx. 3.75 inches long) 4 cardboard wheels, 1.5 in. diameter One 3-oz. paper cup Calculator Scissors Rulers Tape measure Stop watch Tape Wooden or foam board (or any type of flat surface suitable for a ramp) 30 washers (3/8 in.) Books for stackingPer class: BalancesProceduresPart 1 (2, 45-min cl
11、ass periods)1. Distribute materials to each group.2. Have students build the milk carton car by following the directions provided in the Additional Resources section of their student handout. 3. Have students build the test ramp as illustrated the student handout.4. Go over Figure 2 with the student
12、s to make sure they understand what they will be measuring as their car rolls down the ramp. 5. Discuss with the class why it is often important to do several trials during experimentation. Draw the students attention to Table 1 in their handout and help them understand where they will be recording
13、their measurements. 6. Have the students roll their car down the ramp three times each for the three different ramp heights 0.1 m, 0.2 m, and 0.3 m. For each trial, have the students measure the time it takes their car to roll down the ramp and how far the car rolls once it reaches the bottom of the
14、 ramp. Make sure the students measure the distances in meters and not centimeters. Have them record all of their measurements in Table 1. 7. Instruct students to calculate an average time and distance traveled for each ramp height and record it in the appropriate space in Table 1. 8. Have students m
15、ass their milk carton cars and then record it in Box #1 in their handout. Make sure students understand that the mass needs to be in kilograms. Point out the conversion in their handout that there are 1000g in 1 kg.9. Have the students read about potential energy in their handout and then have them
16、explain what it means in their own words. Ask the students to predict whether or not their car will have the same or different potential energy when the height of the ramp changes.10. Have the students calculate the potential energies of their cars at the three different ramp heights. Instruct the s
17、tudents to record their calculated potential energies in Table 1. Kinetic and Potential Energy Lesson Plan 3Part 2 (1, 45-min class period)1. Have the students read about kinetic energy in their handout and then have them explain what it means in their own words. 2. Help the students understand that
18、 because kinetic energy is the energy of motion, an object at rest does not have kinetic energy. For their milk carton cars, this means that vinitial=0.3. Tell the students that in order to find the kinetic energy of their milk carton cars at the bottom of the ramp, they need the velocity of their c
19、ars when it reaches that point. Allow the students to work through the series of questions in their handout that walks them through finding the velocity (vfinal). 4. If needed, clarify the purpose of using the ramp ratio (R) and what it means. Instead of using angles and trigonometry in this activit
20、y to find acceleration, the ramp ratio is used. Help the students understand Figures 3 and 4 and how the ramp ratio is directly related to the angle the ramp makes with the ground. 5. Since it will be easy for students to get bogged down in the calculations involved in this activity, remind them tha
21、t the reason for finding the ramp ratio is to calculate the acceleration, which is needed to find the velocity of the cars. Once the velocity is known, the kinetic energy of the cars can be found. 6. Have students calculate R (ramp ratio) and the acceleration for each ramp height. These values shoul
22、d be recorded in Table 2.7. Instruct the students to complete Table 3, which asks for vfinal for each height. Students should then calculate the kinetic energies of their cars to complete Table 4. Part 3 (1, 45-min class period)1. Have the students make a prediction about what they think will happen
23、 when they add weights to their car. They should record this prediction in their handout. 2. Have the students follow the directions in their handout to find out what happens as weight is added to their cars. 3. Help the students to understand that when they add weights to their car, they are manipu
24、lating the mass term in the kinetic and potential energy equations.4. The students can fill in the first row of Table 5 given their previous data.5. Have the students mass one of their washers and then calculate the total mass of their car with the 6 and 12 washers. 6. Have students calculate vfinal
25、 and KE of the car for each of the masses.Part 4 (Variable)1. Assign the questions in Part as a small group discussion activity or as a homework assignment. 2. Discuss the questions as a class. Kinetic and Potential Energy Teacher Notes 1Kinetic and Potential Energy (Teacher Notes) (An Introduction
26、to the Physics of Motion through the use of Milk Carton Cars)General Lesson Notes Units in this activity. Please make sure that the students measure all distances in meters (and not centimeters) and convert all measured masses in grams to kilograms. Variables, constants, and equations. distance (d)
27、has units of meters time (t) has units of seconds mass (m) has units of kilograms height above ground (h) has units of meters velocity (v) has units of m/s acceleration (a) has units of m/s2 ratio of the ramp (R) has is unitless acceleration due to gravity (g) is 9.8 m/s2 Kinetic energy (KE) has uni
28、ts of J Potential energy (PE) has units of J KE = mv2 PE = mgh v = d/t vfinal = vinitial + a*t R = (height of ramp)/(length of ramp) a = g*R Basic physics concepts. Most of the concepts included in this activity are explained in detail in a middle school physical science or high school physics text
29、book. Therefore, extensive explanations about velocity, acceleration, and gravitational acceleration are not included in the teacher notes for this activity.Part 1 Notes Potential energy. The potential energy of an object is the amount of energy stored in that object as a result of it being displace
30、d a given height. Potential energy of an object depends on both its mass and its height above the ground. Mass of milk carton cars. A good ballpark figure for the mass of the milk carton car is about 0.0175 kg. However, depending on whether or not you vary any of the materials for the cars, you will
31、 need to have your students mass their cars so they can compute the PE and KE. Measuring times and distances. Please consult Figure 2 in the student handout to help students understand where and when they need to record times and distances in this activity. Make sure students understand that time ne
32、eds to be measured only while the car is on the ramp. Also, make sure the students only measure the distance from the bottom of the ramp to where the car comes to a stop on its own stops - they should not include the length of the ramp in their measurement of the distance the car traveled once off t
33、he ramp.Kinetic and Potential Energy Teacher Notes 2Part 2 Notes Kinetic energy. Kinetic energy is the energy associated with a moving object. As your students will see in this activity, the kinetic energy of an object depends upon both its mass and how fast it is moving. Rationale for using Ramp Ra
34、tio. The ramp ratio (R) is used in this activity as an alternative to using the basic trigonometry that would normally be used to find the y component of the gravitational acceleration for an object rolling down an incline. Here is the derivation:sin = ramp oflengthiay = g sin (Recall that there is
35、no x component to gravitational acceleration.)F = mamg sin = maa = g sin a = g ; R = rap oflenthi ramp oflengthia = g RPart 3 Notes Mass of washers. Depending on the type of washers you use, the masses will vary. A good ballpark figure is 0.0066 kg (or 6.6 g) per washer. Part 4 Notes Relationship be
36、tween kinetic and potential energy. (This explanation pertains to questions #35 to #41 in the Student Handout) While energy is never created nor destroyed, it most certainly is converted from one form to another. In this activity your students build a car made from a milk carton. This car is be plac
37、ed at the top of a ramp and released. Before the car starts to descend the ramp, it has potential energy associated with its height above ground; however, it has no kinetic energy because it is not moving. Once the car starts to roll down the ramp, it picks up speed (accelerates). Thus the potential
38、 energy of the car is converted into kinetic energy. Once the car reaches the bottom of the ramp, all of its potential energy has been converted into kinetic energy. In addition to calculating the kinetic and potential energy of a milk carton car, your students should be assisted in seeing the relat
39、ionship between kinetic and potential energy, and how the mass of the car affects its kinetic and potential energy.Notes on Materials Materials. Most of the materials listed in this lesson plan can be found at a standard store. The washers, axles, and cardboard wheels could be purchased at a hardwar
40、e store.Kinetic and Potential Energy Student Handout 1Penn State University GREATT ProjectName:_Kinetic and Potential Energy (An Introduction to the Physics of Motion through the use of Milk Carton Cars)OverviewDuring this activity you will build a car using a milk carton and then observe how this c
41、ar behaves as it travels down a ramp. You will learn about kinetic and potential energy so that you can explain what you observe. Have fun!Part 1 (What is potential energy?)1) Build the milk carton car as described in the Additional Resources section of the handout.2) Use the wooden board (or some o
42、ther flat surface) and a stack of books to create a test ramp. Be able to adjust the height of the ramp to 0.1, 0.2, and 0.3 meters. Keep in mind that 0.1 m = 10 cm0.2 m = 20 cm0.3 m = 30 cm3) Set the ramp height to 0.1 m by adjusting your stack of books appropriately. (Refer to Figure 1.) HEIGHT Ra
43、mpFigure 1. Ramp height.4) Now take some time to study Figure 2. Figure 2 describes the two things you want to measure as you as you observe your car go down your ramp. a) The time it takes for your car to roll down the ramp.Kinetic and Potential Energy Student Handout 2Penn State University GREATT
44、Projectb) The distance your car travels from when it reaches the bottom of the ramp to when it comes to a complete stop on its own.You will want to record both of these measurements in Table 1.HEIGHT Figure 2. Car and ramp, showing where to begin timing and measuring.Notice from Figure 2 that the ti
45、me you are measuring only involves the time your car spends on the ramp. It does not include any time your car spends rolling once it is off the ramp.Also notice from Figure 2 that the distance you are measuring does not include the length of the ramp. Only measure the distance between the base of t
46、he ramp and the point at which your car comes to a stop by itself.5) Obtain the time and distance for each ramp height (0.1m, 0.2m, 0.3m). To reduce error, measure the time and distance three times for each height. Record all of your data in Table 1. 6) Compute the average time and average distance
47、for each ramp height and record these values in the gray shaded area in Table 1.7) Mass your car on a balance, and record it in the appropriate space in Box #1. Notice that you need to record this value in kg, so remember that1000g = 1kg.8) Read about potential energy in the Additional Resources sec
48、tion of this handout. Describe what potential energy means IN YOUR OWN WORDS. Use the box provided.In my own words, potential energy means.Begin timing hereEnd timing here;Begin measuring distance from here Kinetic and Potential Energy Student Handout 3Penn State University GREATT Project9) Will you
49、r car have the same or different potential energy when the height of the ramp changes? Make your prediction in the box provided.10) Using the information provided in Box #1, compute the potential energy (PE) of your car when it was sitting at the top of the ramp. Show your work for this calculation in Box #2, and then record this number in the appropriate space in Table 1.Box #1. Equation for potential energy.Box #2. The PE of my car when the ramp height is 0.1 meters.11) Repeat
