Topic outline
- General
General
Conceptual Physics is a course designed to teach the important concepts in physics, such as motion, forces, work, machines, and energy. Later in the year, students will learn about waves, sound, light, electricity, and magnetism. The course is less math-intensive than the Physics course, but still covers all of the same topics.
We use the Prentice Hall textbook "Physical Science - Concepts in Action"
Use the following link to access the online textbook help site, which includes short chapter quizzes and answers.
On that web page, students can also enter the Web Codes that are located on various pages of the textbook (for example, code ccc-0013 found on the upper right of page 15.) - Topic 1
Topic 1
Chapter 1: Science Skills
Major concepts:
Branches of Science
Scientific MethodObservations - Problem - Hypothesis - Experiment - Data - Results - Conclusion - check Hypothesis and keep the cycle going.assignment: Scientific Method in the Real WorldLaws and Theories
A law states what happens, usually in a mathematical formula. Examples: Acceleration = Force divided by mass; E = mc2Metric System and Scientific Notation
A theory explains how or why something happens. Theories are much stronger than hypotheses, since they are supported by many experiments and many scientists. Scientists understand the laws of gravity very well, but they still don't have a good theory about exactly what causes one object to pull on another. They can calculate the earth's magnetic field very precisely, but they are not sure what causes it. Other theories such as plate tectonics or star formation are very well formed.
Units (gram, second, meter, liter, etc.)
Major Prefixes: Mega = million kilo = 1000 centi = .01 milli - .001(Scientific Notation tutorial in the textbook Math Skills appendix)
Scientific Notation is just a convenient way to express very large or very small numbers.Precision and Accuracy
Precision is how exact a measurement is, or the smallest unit used in the measurement; for example, if you measure someone's weight rounded off to the nearest ten pounds ("160 pounds"), it is useful, but a measurement to the nearest half pound ("158.5 pounds") is more precise. Precision is limited by the measuring tool used. You can't use a clock on the wall to measure milliseconds, but you can measure to the nearest second.Graphing
Accuracy is how correct an answer is, or whether it agrees with the accepted value. An answer can be very precise, but not accurate, and therefore not very useful. Example: "The height of the ceiling in the classroom is 5 feet, 2 and 3/16 inches." Very precise, but completely inaccurate, and WRONG! Accuracy matters more than precision.
- Topic 2
Topic 2
Chapter 11 - Speed, Velocity, and Acceleration
Reference frame (or frame of reference): The system of objects you base your measurements on. What locations and speeds you call "zero" For example, you could measure the velocity of an object relative to the classroom, or relative to the bus seat you are riding in.
Vector: a measurement with both a size and direction. The size is called the magnitude. Examples: velocity = 24 mph, east Force = 240 Newtons, down
Scalar: A measurement which has a magnitude, but does not have a direction. Examples: temperature = 58 degrees Celsius mass = 24 kgSpeed = distance / time Average speed = total distance / total time
Instantaneous speed = speed at one instant, one tiny moment in time
Velocity = Speed AND Direction (example 24 m/s, east)
Acceleration = Change in Velocity / Change in Time usually measured in meters/second/second, or m/s2
An object accelerates by changing its velocity (speed and direction), which means it can change speed or direction or both. It can speed up, slow down, or change direction (turn). We don't feel when we are moving, but we can feel when we accelerate. Example: travel in a car at 60 mph, and you can sip from a cup of soda just fine, because you're not accelerating. But if the driver suddenly speeds up, slows down, or turns, you've accelerated, and you usually spill the soda.
- Topic 3
Topic 3
Chapter 12: Forces, Newton's Laws, Gravity
Big concepts:
- What are the different types or sources of force?
- How is adding forces different from adding masses?
- What exactly is "an equal and opposite reaction"?
- What is momentum and how is it conserved?
- Why does the moon stay in its orbit instead of flying off or crashing into the Earth?
- Chapter 13: Forces in Fluids
Chapter 13: Forces in Fluids
Measure pressure of different fluids at different depths. See what happens when metal weights push down on fluid in cylinder.
- Chapter 14: Work and Machines
Chapter 14: Work and Machines
Chapter 14: Work and Machines
Big Concepts: Work is done by a force moving an object. Machines change the way work is done by changing the input force and displacement. Machines always use up some of the input work, losing it to heat due to friction.
Work = Force • displacement, as long as the force and displacement are in the same direction. (Remember that displacement is just the vector form of distance, which includes direction.)
Ex: Push with a force of 40 Newtons to move a box 3 meters.
Work = F • d = (40N)(3m) = 120 N•m = 120 Joules
Power = Work / Time [Units: Watts = Joules / Seconds
Simple Machines either trade force and distance, or they change the direction of a force, or both. They do NOT put out more work than you put in.
Interactive Basic Gears Demonstration
Great Rube Goldberg Machine from Baynham Tyers
In the engine animation to the right, notice such things as the directions the gears turn and the timing of each colored cam, which controls when the valves open and close.
Define these in your own words, with examples.
- Topic 6
Topic 6
Energy - Chapter 15
Big Concepts:
Energy comes in many forms. It can be converted from one form to another, but it is always conserved (it never disappears).
Major Types of Energy
Kinetic = "moving" KE = Kinetic Energy
Mechanical KE = 1/2 mv2 Example: flying baseball or moving carPotential = "stored" PE = Potential Energy
Heat: KE of atoms or molecules
Sound: KE of particles vibrating as a compressional wave passes through
Gravitational PE: stored in raised objects (such as a rock on a high ledge)
Formula: GPE = (mass)(acceleration of gravity)(height)Chemical PE: stored in chemical bonds between atoms (such as food or gasoline)
Elastic PE: stored in bent, stretched, or compressed objects (such as stretched rubber bands)
Nuclear PE: stored as mass E = mc2 Example: Uranium in atomic bomb
Electrical PE: stored in separated opposite charges, or in like charges stored together Example: protons and electrons separated in capacitorElectromagnetic Energy
Usually in the form of light, which is electromagnetic waves. Light can be visible (red, green, blue, etc.) or invisible (radio, ultraviolet, x-rays, etc.) depending on its frequency.
Chapter 15 Test: Energy - Topic 7
Topic 7
Wave Basics - Chapter 17
1. Mechanical Waves: Definitions and Types
- Waves are traveling vibrations which carry energy from one place to another.
- Waves can be either Transverse or Longitudinal. (Longitudinal waves are also called Compressional). There are also more complicated waves such as surface waves, which combine transverse and longitudinal motions.
- Look at the Wave Animations, and decide what directions the are moving, and what directions the particles are moving for each wave type.
- Transverse waves: highest point = crest lowest point = trough
- Longitudinal waves: densest point = compression least dense point = rarefaction
2. Mechanical Wave Properties
Play with the PhET lab "Waves on a String" to familiarize yourself with some ideas and terms. Click the buttons! Experiment!Phet Lab Instructions: Waves on a String
- All waves have period and a frequency. The period is the amount of time that passes between identical waves. The frequency is the number of waves in a certain amount of time. The basic unit of frequency is the Hertz (Hz) which equals waves per second.
- To get the concept of period, it is useful to study a pendulum.
- All waves have a wavelength, which is the distance from one point on a wave to the matching point on the next wave. (Example - distance from crest to crest, or trough to trough.)
Thanks to Dr. Dan Russell at Kettering University for his great web site with many animations! http://www.kettering.edu/~drussell/demos.html
3. Wave Behavior
Once you get the major concepts down, you can study the more interesting (and more difficult) topics such as:- Reflection - bouncing off a barrier
- Refraction - bending as a wave enters a new medium
- Doppler Effect - shifting of frequencies and wavelengths due to motion
- Interference - adding of two waves which either get larger or diminish each other
- Topic 8
Topic 8
Sound - Chapter 17 continued
Important Concepts
- Sound is a compressional, or longitudinal, wave. This means it is produced by something vibrating back and forth in the same direction the wave is traveling.
- The frequency of a sound wave controls its note, or pitch.
- The amplitude of a sound wave controls its loudness, or volume.
Virtual Oscilloscope web site: See the tones!Sound waves can interfere with each other. This can lead to interesting phenomena such as noise canceling headphones, and beats from musical instruments.
Sound from a Vibrating String
General Sound Animations - ltscotland.org.uk
- Topic 9
Topic 9
Visible Light and Other Electromagnetic Waves - Topic 10
Topic 10
Electricity - Topic 11
Topic 11
Magnets and Electromagnetism - Topic 12
Topic 12