Also next week, you will have your first formative where you will learn how to use the testing website.
So let's get to it.
CLICK HERE
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Housekeeping: We are now moving into the content. We begin with an introduction to chemistry and the concept of matter. My expectation is that we will spend about four weeks on this unit. You will have your first lab next week.
Also next week, you will have your first formative where you will learn how to use the testing website. So let's get to it. CLICK HERE
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Housekeeping: Welcome back to school!
Agenda: Welcome Introduction to the course Class procedures Housekeeping (5 min) Warmup & review (10 min) Missions (20-25 min) Wrap-up/homework (5 min) Navigating the website (Where to find…?) CLICK HERE We will use PhysicsTracker to analyze the Hot Wheels data. You should read through the HowTo and watch the below video to learn how to use it. PhysicsTracker will automatically incorporate Java, so you don't need to download it. After you have downloaded the tracker software, open up a new file and drag your video into the video box. From there, you will calibrate and mark your Hot Wheel as it moves down the track. You're going to have to watch this several times (I did) to get the hang of it. Housekeeping: We are now investigating forces and Newton's Laws. Your last test over this material is May 23. Content Review: Physics Classroom Physics Hypertextbook Uniform & Accelerated Motion Velocity-Time Graphs Readings: Physics Hypertextbook, 2.1, 2.2, 2.3, & 2.6 Glencoe: Forces Student Missions: Mission 1: It's All Newton's Fault Mission Objectives: You should be able to... 1. Define "force" and differentiate between contact forces and long-range forces. 2. Recognize the significance of Newton's 2nd and use it to solve motion problems. 3. Explain the meanings of Newton's 1st and 3rd and provide examples. 4. Draw and explain free-body diagrams. A force is a push or pull on a stationary object. There are two types: contact and long-range. Contact forces act on an object by touching it. Example: you touching your laptop. A long-range force is exerted without contact. Example: magnets and the force of gravity. How to draw a free-body diagram. How to calculate the net force using free-body diagrams. Newton's Laws of Motion. 1st: An object at rest will remain at rest unless acted upon by a force, or an object that is in motion will continue to move in a straight line unless acted upon by a force. Example: A soccer ball sitting on the pitch will not move unless it is kicked. A car in motion will remain in motion until it is acted upon by a force. This law is commonly called the law of inertia. Inertia is the tendency of an object to resist change. If the net force on an object is zero, then the object is in equilibrium. Below is a table showing the different kinds of forces. 2nd: Force = mass X acceleration. The larger the force, the greater the acceleration. As mass increases, the greater the force required to move the object. 1st image: bitlanders.com 2nd image: zonaleducation.com 3rd. An interaction pair is two forces that are in opposite directions and have equal magnitude. All forces come in pairs, act on different objects and are equal in magnitude and opposite direction. See the image below. The action of stepping off the boat is equal to the reaction of the boat moving backwards.
Image from wired.com EC2 will be joining us at 11:40 today to learn more about inclined planes and forces. Basically, you should explain how your race track works and have them identify which portions of the track are inclined planes (you're supposed to have at least one). If you know nothing about inclined planes, go here.
They are also learning about forces. Basically, they're learning about F = ma, which is Newton's second law. Force = mass of object times acceleration. You guys apply a force to start your Hot Wheel on the track, and hopefully the force is enough for the Hot Wheel to complete the track. Some of you are using your hands and others are using the launcher. If you are able to do both, show the students both ways and have them predict which yields the greater acceleration. Run this lesson with each of your cars and explain why you get different results for each car. Of course, let them play with your tracks, ask them questions about what they've learned, and encourage them to explain back to you what is going on with the track. Ask them about Newton's 2nd and how to apply forces. Basically, you're having them summarize the lesson. Housekeeping: We are now investigating accelerated motion. While you're learning the material in class, you will also be working on designing the most efficient Hot Wheels track system that you must use to calculate velocity and acceleration of the cars. Instead of an actual lab write-up, you and your team of engineers will submit the actual design that you will use. Content Review: Physics Classroom Physics Hypertextbook Uniform & Accelerated Motion Velocity-Time Graphs Student Missions: Mission 1: Speed Demon Mission Objectives: You should be able to... 1. Define "acceleration" in your own words. 2. Calculate acceleration given position & time graphs 3. Draw and interpret an acceleration-time graph 4. Use the motion equations in problem solving. Let's backtrack for a few minutes. I forgot to talk about displacement. Basically, distance is a scalar quantity that describes movement between locations over an actual path connecting them. Displacement is a vector quantity that describes movement between locations over the shortest path connecting them. So if you were to do one lap on a standard track (400 m) and return to where you started, your distance would be 400 m, but your displacement would be 0 m because you ended up exactly where you began. Take a look at these practice problems. Try to solve them before checking your answers. I introduced the concept of acceleration last Wednesday, but we're really going to get into it this week as part of your prep for the Hot Wheels lab. Before we do that, let's watch this clip from the movie Armageddon. What you're seeing is the acceleration of the shuttles to reach maximum velocity in order to catch up with the asteroid. The pilots used the gravity of the moon as an assist to reach the maximum velocity of 22,500 mph. For the record, NASA went metric back in 1990 (this movie came out in 1998). Convert 22,500 mph into kilometers per hour. What do you get? Also, for the record, they shouldn't be able to breathe at that speed, much less scream. The immense G forces over that length of time should crush their lungs to the point where they can do little more than gasp for air and likely pass out. The maneuver would very likely kill them. However, this was a totally fun movie (in spite of the crap science) and I had a blast watching it in the theater. Now, let's get into the actual science of acceleration. This week, you guys will experiment with velocity and acceleration using Hot Wheels. You have to determine the velocity and acceleration of the cars using the track you're given. You also need to familiarize yourself with PhysicsTracker so that you can upload your videos and analyze the data. Practice Problems You'll start preparing for your first motion quiz (May 2) by completing the below assignment. Things to remember: 1. If the line slopes away from the x- (or time) axis, it is gaining speed; if it slopes towards the x- (or time) axis, it is losing speed. 2. If the velocity-time graph lies in the 4th quadrant, then the object is losing or gaining speed in a negative direction. Also: gaining speed (+) in a positive (+) direction + acceleration gaining speed (+) in a negative (-) direction - acceleration losing speed (-) in a positive (+) direction - acceleration losing speed (-) in a negative (-) direction + acceleration Source For the following exercise, you will work on your own. You have 45 minutes to complete the problem. You may use your notes. You are given the following data. Do the following: (1) Calculate velocity and acceleration. (2) Graph position, velocity, and time. (3) Describe the velocity and acceleration graphs in terms of gaining/losing speed and +/- direction. Make sure each graph has a title and labeled axes with units. Remember that you must have three separate graphs. Use Excel to do the calculations and graphs. Put everything in one document and upload it to Managebac under "Motion Practice Problem." After you have uploaded your work, go ahead and work on your race track. This is how I want you to set up your Hot Wheels presentation. You will submit this on Friday at the beginning of the period. Today (May 15) is your last day to work on your Hot Wheels track.
Housekeeping: We are now investigating uniform and accelerated motion. Your test on waves is scheduled for April 18, 2018. It is on you to make sure you're re-reading the waves content on the website and in your reading packet to prepare for the test.
For this unit, I am giving you three (3) packets, which contains the notes you'll need to fill in. Below, in Content Review, I have included a link to an online physics textbook that you will find useful (and that I'll assign readings from when necessary). Content Review: Physics Classroom Physics Hypertextbook Uniform & Accelerated Motion Velocity-Time Graphs Student Missions: Mission 1: Where You Stand vs. The Way You Move Mission Objectives: You should be able to... 1. Define the following terms: distance, displacement, speed, velocity, acceleration, vector, scalar, uniform motion, and accelerated motion. 2. Construct and interpret postion-time graphs. 3. Construct and interpret velocity-time graphs. Let's watch a video of Usain Bolt smashing the 100m dash.
How did he do it? Let's investigate!
So let's get into it. Before you watch this video, be sure to complete the first objective for Mission 1: Define the following terms: distance, displacement, speed, velocity, acceleration, vector, scalar, uniform motion, and accelerated motion.
Then go to the Hypertextbook and read Kinematics 1, 2 & 3. After that, watch the video.
Let's play around with the concept using pHet's Moving Man Simulation.
Let's Practice!
Check Yo' Work! Acceleration is merely the change in velocity divided by the change in time. We are going to revisit an earlier video so that you can learn to calculate acceleration given position and time. Then you will work on graphing all three quantities.
Housekeeping: We are now studying waves. You will be given a "textbook" that contains your readings and whatever practice problems you'll need.
Content Review: BBC Bitesize colorado.edu Student Missions: Mission 1: Wave Properties Mission Objectives: You should be able to... 1. Explain how waves transfer energy without transferring matter. 2. Compare & contrast longitudinal and transverse waves. 3. Relate wave speed, wavelength & frequency
First of all, watch the above video. Secondly, read Section 14.1 in your textbook. It covers wave basics. You are expected to know the vocabulary. You will investigate waves using springs using the design lab on page 330. You will take measurements on amplitude, wavelength and frequency. You need to be able to calculate the speed of the wave you generate (page 333 shows you how to do this) with the spring.
You will eventually submit a research question, hypothesis, data, analysis and conclusion, but not today. You cannot use the RQ and hypothesis listed on page 330. Once you are done with the activity, begin working the problems on page 335. Use the below to help you with organizing your data and complete calculations.
Play around with waves using this simulator. Or this one.
Mission 2: Wave Behavior Mission Objectives: You should be able to... 1. Relate a wave's speed to the medium in which it travels. 2. Explain the concept of interference. 3. Describe how waves are reflected and refracted at boundaries between media and explain how waves diffract. 4. Apply the principle of superposition to the phenomenon of interference. 5. Predict the shape of a wave formed by interference. Section 14.2 covers wave behavior. Make sure you read it and get all the vocabulary down.
Below is a pHet simulation on wave interference. Play around with it. Below that is another powerpoint that goes into detail about refraction, reflection, interference and diffraction.
Mission 3: Something Snells Up in Here!
Mission Objectives. You should be able to... 1. Explain Snell's Law. 2. Solve problems using Snell's Law.
Let's practicesolving Snell's Law problems.
The exam over energy is currently scheduled for February 14, 2018.
For the next two weeks, you guys will work on this semester's research project. You and one other person will investigate one of the following sources of energy: Biomass Brennan and Raymond Solar Energy Andrea and Ariel Wind Energy Caitlin and Ie Geothermal Energy Thomas and Yong Ki Hydroelectric Energy Dave 2 and Nikita Tidal Energy Ken *3 and Narayan Ocean Wave Energy Putri and Sharon Nuclear Power Dave 1 and Alifia Fossil Fuels Izzy and Anais Hydrogen Energy & Fuel Cells DZ and Arif Outline your paper according to the following: I. Introduction. Define and discuss energy in general terms. End your intro with a statement about which energy topic your paper will focus on. This is your thesis statement. II. Body paragraph 1. Introduce your topic. Provide examples of where it is used and how. III. Body paragraph 2. Discuss the pros and cons of your energy topic. IV. Conclusion. Summarize the paper. Evaluate the research that you have examined and discuss the its implications. In other words, do you believe your energy topic is a viable alternative? Back up your opinion with facts and include citations. Your presentation has two components: a 2-page essay and a class presentation. I will distribute rubrics so that you have a format to follow. Presentations will take place during the week of February 5 - 9, 2018. A rough draft of the essay is due February 5. Final drafts are due February 14. Housekeeping: We will be covering thermochemistry and energetics this month. I have two reading packets from two different textbooks that I will give you. It is your responsibility to keep up with your packets and bring them to class every day. I will give you reading assignments and problems from the packets. Agenda: 1. Heat vs Temperature 2. Specific Heat 3. Enthalpy Content Review: Student Missions: Mission 1: ENERGY!!! Mission Objectives: You should be able to... 1. Define "energy." 2. Distinguish between potential energy and kinetic energy. 3. Explain the law of conservation of energy. 4. Understand specific heat and solve problems. Energy is the ability to do work or produce heat. In physics, energy is the ability to do work. In chemistry, energy is the ability to produce heat. It exists in two forms: potential energy (PE) and kinetic energy (KE). The total amount of energy in a system does not change because energy cannot be created or destroyed; it just changes between KE and PE. Potential energy is the energy of position and kinetic energy is the energy of motion. Potential energy of a substance depends on its composition: kind of atoms in the substance, number and type of chemical bonds connecting the atoms, and the atomic arrangement. Energy is stored in the bonds holding the atoms together. The first law of thermodynamics is the same as the law of conservation of energy: energy can be converted from one form to another (PE to KE; KE to PE), but it is neither created nor destroyed. Heat is energy that flows from a warm object to a cool object. Temperature is the measure of the average kinetic energy of molecules. They are not the same. Temperature depends on the amount of heat transferred to or from an object, the mass of the object, and the specific heat of the object. Specific Heat is the amount of heat required to raise the temperature of one gram of a substance by one degree Celsius. Substances have unique specific heats. Below is the equation for calculating specific heat. Units for specific heat are J/(g * C). Professor Dave is on the case. Practice problems: Specific Heat 1 Specific Heat 2 Mission 2: The Cup Is Hott!!! Mission Objectives. You should be able to... 1. Describe how a calorimeter works. 2. Explain the concept of system and surroundings. 3. Define "thermochemistry." A calorimeter is an insulated device used for measuring heat absorbed or released during a chemical or physical process. A known amount of water is placed inside the calorimeter to absorb the energy released from an immersed substance. Data that's collected is the change in temperature of the water. When the substance and water have the same temperature, that is when the process stops and the specific heat of the substance can be determined. You guys will be experimenting with calorimetry and specific heat next week. Please start bringing in snacks such as peanuts, snack bars, Cheetos, dried fruits, etc. I also need 10 volunteers to bring in an empty uncrushed soft drink can. You will determine the energy content of the snacks using a bootleg calorimeter. You will also identify metal samples via their specific heat using a bomb calorimeter. Thermochemistry is the study of heat changes that accompany chemical reactions and phase changes. The burning of fuels always produces heat. Some products are engineered to produce heat on demand, such as heat packs. On page 525, you will see an equation for the production of heat in a heat packet. Notice where the energy lies. Because heat is produced, the energy is on the product side. On page 528, you will see an equation for the production of "cold" in a cold packet. Notice where the energy is. Because heat is absorbed, energy is on the reactant side. Exothermic reactions release heat. Endothermic reactions absorb heat. We are not done talking about these terms. Since it is difficult to know the total energy content in a substance, chemists have focused on the changes in energy. Enthalpy (H) is the heat content of a system at constant pressure. The change in enthalpy, which is the heat absorbed or released, can be measured. The change in enthalpy for a reaction is explained on page 527. HOMEWORK: Mission 1: p. 552, #53-56, #58, & #61 Mission 2: p. 552: #68-69, #73-78 Exothermic reactions release heat when bonds are formed. Endothermic reactions absorb heat to break bonds. Phase changes that are endothermic: melting, boiling and sublimation. Phase changes that are exothermic: condensation, freezing and deposition.
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