Table of Contents
A syllabus is an overview of what material will be covered in a class. In the first half of the year, we will be covering the branch of physics called "Dynamics:" the study of how objects move around and interact. In the second half, we will get to look at a wide variety of other parts of physics, including light and optics, color, heat, sound, and electricity and magnetism.
In the first half of the year, all the topics build on one another; you have to be good at what we did in a previous chapter in order to do well on the rest. In order to give you all a big advantage coming into that part of the year, we're doing a long unit on Units, which will give you skills with which the rest of the semester will be much easier. One of my heroes, the physicist Richard Feynman, once wrote that he was able to accomplish such impressive things as he did primarily because he had in his mind a small toolbox full of tools useful for physics, and he knew each of those tools well. When I think over what tools are in my own toolbax, unit manipulation stands out as the singularly most useful, and the one I most want to pass on to you.
1. Units and Dimensional Analysis2 weeks - Unit Overview - Detailed Notes
In science, you rarely deal with plain numbers; instead of just "4", you have something like "4 inches" or "4 days". Is this extra information, the "units" of the number, useful, or is it just a nuisance, another thing we have to remember to include when we write the number?
In this unit (ha!) we will learn how to turn our units from something that requires extra work and worry into something that does work for us. You will be amazed to discover that, if you know a few tricks using units, you will be much less likely to make mistakes in the math you do in science class. In fact, you will be able to figure out most of what we'll do in the first half of the course, simply from doing tricks with units. If it weren't for Dimensional Analysis (which is what one of those unit tricks is called), Mr. Z. would have failed a lot of important physics tests.
- Why is it important to use units in our measurements?
- How do we convert from one type of units into another?
- What unexpected problems might we run into in converting units?
- What do we get when we add or multiply numbers that have units attached?
- How can units be used to check that an equation is correct?
- How can units be used to figure out what the correct equation for something is?
- What units are used for some important sorts of measurements in science and specifically in physics?
- How can we figure out what variables matter in an experiment and what their units are?
- How can we set up an experiment to prove a particular equation to be correct or incorrect?
- What tools can we use to analyze data?
- How close agreement with theory is close enough (How big do we expect errors to be)?
2. Linear Motion2-3 weeks
An object in the real world, like a football, can move around in three dimensions while simultaneously tumbling around in three different directions at once. We don't want to have to deal with all that complexity to start out with. So, our Kinematics unit deals just with things moving along a single line, like cars on a road. You'll be surprised at how many things can be described just by this simple model.
- Distinguish between, and solve problems involving, velocity, speed, and constant acceleration.
- Create and interpret graphs of motion (position vs. time, speed vs. time, velocity vs. time, constant acceleration vs. time).
3. Projectile Motion1-2 weeks
When we allow ourselves to consider things moving in two directions at once, a lot of new possibilities appear. For example, a basketball, when thrown through the air, traces out a parabola, which of course is two dimensional. The ball is going up into the air, then falling down, a motion in the vertical direction. But it is also traveling across the court, a motion in the horizontal direction. We will discover that the techniques we used in Linear Motion will solve these problems as well, if we just think of them in terms of two linear motion problems happening at once.
As part of this unit, we will study vectors, which you may or may not have used before in math. The will give us another useful tool that will be helpful in the next two units.
- Distinguish between vector quantities (velocity, acceleration, and force) and scalar quantities (speed and mass).
- Illustrate how to represent vectors graphically and be able to add them graphically.
4. Force and Inertia2 weeks
So far, we've just talked about objects that are moving an accelerating in certain ways, without trying to explain why they are moving like that. But physics is always trying to find out the causes of things, which is why I put that quote from Vergil so prominently on the main page of the website. When we ask about what causes motion to change, we discover that it is a result of a "Force," a push or pull on some object.
We also learn about Inertia, or Mass, which is the property of an object that makes it want to resist having its motion changed. If you push a shopping cart as hard as you can, you can get it to go rattling across a parking lot at a high speed. If you push just as hard, just as long against a large car, you will barely get it to move.
- Explain the relationship between mass and inertia.
- Interpret and apply Newton’s first law of motion.
- Interpret and apply Newton’s second law of motion to show how an object’s motion will change only when a net force is applied.
- Use a free body force diagram with only co-linear forces to show forces acting on an object, and determine the net force on it.
- Qualitatively distinguish between static and kinetic friction, what they depend on and their effects on the motion of objects.
- Interpret and apply Newton’s third law of motion.
- Understand conceptually Newton’s law of universal gravitation.
- Identify appropriate standard international units of measurement for force, mass, distance, speed, acceleration, and time, and explain how they are measured
5. Momentum2-3 weeks
It might seem strange to you that you can catch a baseball traveling at 40 mph and not be hurt a bit, but if you're hit by a bus traveling at the same speed, it might kill you. In order to deal with situations like this, an to explain why a heavy object moving quickly is much more dangerous than a light object, physics introduces the idea of Momentum. We will use this idea primarily to deal with collisions and similar events.
Changes in Momentum are another one of the things that can be thought about as a cause of a Force. After all, when you get hit by a car, it certainly pushes against you, and when you increase the momentum of a shopping cart to get it moving, it certainly takes some Force. This unit will help us to understand why, when you get tackled in football, you want to relax as muh as possible to reduce the Force and thus reduce your chances of getting hurt.
- Interpret the law of conservation of momentum and provide examples that illustrate it. Calculate the momentum of an object.
6. Energy2 weeks
As we delve deeper into what causes Force, still looking for the root cause of things, we come to the concept of Energy. in a sense, Energy is what makes all things happen. Electrical energy lights up this room; potential energy makes a meteor fall; chemical energy runs cars and buses. Energy is an idea that you will not only in physics, but also in chemistry, biology, and any other science class you take. In this unit, you will learn how to visualize a situation in terms of an exchange of energy.
- What is energy?
- What are some of the forms of energy?
- How can energy help us figure out what will happen in some situation?
- How can we represent more abstract types of energy as simple hills?
- What is work?
- How do tools like a hammer or stapler help you do something that would be difficult with just your hands?
- Where does the energy that we use come from?
- What happens when energy changes form?
- Relate thermal energy to molecular motion.
- Differentiate between specific heat and heat capacity.
- Explain the relationship among temperature change in a substance for a given amount of heat transferred the amount (mass) of the substance, and the specific heat of the substance.
- Recognize that matter exists in four phases, and explain what happens during a phase change.
8. Waves and Sound
- Recognize the effects of polarization, wave interaction, and the Doppler Effect.
- Explain, graph, and interpret graphs of constructive and destructive interference of waves.
- Explain the relationship between the speed of a wave (e.g., sound) and the medium it travels through.
- Recognize the characteristics of a standing wave and explain the conditions under which two waves on a string or in a pipe can interfere to produce a standing wave
- Describe the electromagnetic spectrum in terms of wavelength and energy, and be able to identify specific regions such as visible light.
- Explain how the various wavelengths in the electromagnetic spectrum have many useful applications such as radio, television, microwave appliances, and cellular telephones.
- Calculate the frequency and energy of an electromagnetic wave from the wavelength.
- Recognize and explain the ways in which the direction of visible light can be changed.
- Recognize the characteristics of static charge, and explain how a static charge is generated.
- Interpret and apply Coulomb’s law.
- Explain the difference in concept between electric forces and electric fields.
- Develop a qualitative and quantitative understanding of current, voltage, resistance, and the connection between them.
- Identify appropriate units of measurement for current, voltage, and resistance, and explain how they are measured.
- Analyze circuits (find the current at any point and the potential difference between any two points in the circuit) using Kirchoff’s and Ohm’s laws.
12. Other topicsAt the end of the year, we will study various other topics in physics. This will probably take the form of some sort of large project, such as a robotic design competition.