Directions: Your job is to respond to the discussion post by answering my initial questions or following the directions there. You may also receive credit by "constructively and appropriately" responding to a peer response. For example, if a peer responds to my initial questions and/or asks a new question, you can attempt to research, answer their question, or otherwise respond "constructively and appropriately." You will earn a grade for correctly responding to the discussion each week. (Note: After the due date, the discussion will be locked. You may only receive credit by responding by the due date assigned.) Full credit (15 points) will be based on 3 criteria: 1. Completeness of your response (In MOST cases, A FEW SENTENCES SHOULD be sufficient), 2. Significance of contribution (Does your response address my initial post or does it constructively build on the response of someone else?), 3. Reasonably correct spelling and grammar.

Physical Science
What is Physical Science? Please compare and contrast it to other branches of science. What are some of the issues and problems physical scientists are working on today? (please cite the sources you researched / used by including the appropriate links as a part of your response)

Scientific Method
What is the scientific method? How and why is it used? What do you think is the ultimate goal of science?

  1. How and why are careful scientific measurements made using the metric system? Please consider activities we've done in class.
  2. Make up and explain a situation in which you use some type of measuring device to make a correct, accurate, and precise measurement. Explain what the item is that is being measured as well as the precision of the device you measured with. i.e. if using a metric ruler, were the smallest divisions (centimeters, milimeters, etc.)
  3. Then explain why your measurement has the correct precision based on the quantity being measured and the precision of your measuring device.

States of Matter
How many states of matter are there? (*Hint: some of them aren't often talked about in everyday life, and you may have to dig deeper to find out more about them). Your job is to answer: 1. How many states of matter are there? 2. Explain what they are and how they are different from one another.

  1. How does the density of an object compare to whether it floats or sinks in water?
  2. Can objects have equal mass and different densities?
  3. Can objects have equal volume and different densities?
  4. Can 2 different sized objects made of the same material have equal density?

Kinetic Theory of Matter
Explain what it is and provide at least one example of how it applies to everyday life. How does it explain the motion and spacing of particles in the various states of matter? How is it related to heat and temperature? Also, include info on at least one lab or demonstration we’ve seen in class that can be explained by this theory.

Phase Changes
I guess the term "State" of matter is pretty much synonymous with "Phase" of matter. i.e. solid, liquid, gas, plasma, etc. For your response this week, I'd like you to research and describe a Phase Change of your choice. Please visit this link for more info on phase changes:
For full credit (15 points) on your response:
1. Briefly explain the phase change you researched. What is happening to the particles of matter during this phase change? Why?
2. State something unique or interesting about your phase change that you found during your research.
3. Provide the links to your reliable sources

Ideal Gas Laws
  1. What is(are) the ideal gas law(s)?
  2. Compare Boyle’s and Charles’ Laws. How are they similar? How are they different?
  3. What is something you’ve done or seen in class that is related to these laws?

Physical vs. Chemical Properties and Changes
What is the difference between a physical and chemical property? Provide an example of each. How do you know when a physical change has occurred? How do you know when a chemical change has occurred?

Physical Mixture Separation
There are various methods for physically separating mixtures. Explain 3 such methods, and/or constructively build on the response of someone else.

Solubility and Rate of Solution
Solubility is the amount of solute that can be dissolved into a given amount of solvent at a given temperature. Rate of solution is how quickly a solute can be dissolved into a solvent. 1. Solutes can be solids, liquids, and/or gases. As temperature of the solvent increases, explain how the solubility of solid solutes in liquid solvents typically differs from that of gas solutes. 2. What are 3 factors that affect the "rate of solution?" How? Please respond to these questions or constructively build upon the post of someone else. For full credit, I'm looking for completeness, significance and grammatical correctness of your response.

Comparing the Size of Atoms to the Human Scale
Our understanding of matter, energy, and the atom has evolved over time as more and more information has become available and technology has improved. Often you will hear or read that, "most of the atom is made up of empty space." 1. Please explain why this is true by briefly explaining what a typical atom is like in terms of it's mass, volume, etc. 2. Also, research and find 1 interesting/unique fact about atoms. Some examples may include: How many would you need to line up in a row to equal 1 cm? How many make up your body? I don't know.... just something unique and interesting. 3. Finally, please include the URLs for any reliable sources you used. Thanks!

The Periodic Table of ELEMENTS!
An element is defined as the simplest type of pure substance made up entirely of only one type of atom. As time goes on scientists are discovering more and more elements. However, most of the newest elements of the periodic table have been created in the lab and only existed for mere fractions of a second before rapidly decaying. For this week, 1. Choose an element from the periodic table. (The tricky part is each element may only be used once, so make sure you read through your classmates entries before responding) 2. Please provide the following: a. The name of your element and it's chemical symbol. b. The group and period in which your element lies on the periodic table. c. The atomic number of positive protons within each atom of your element. d. Finally, please briefly describe the physical and chemical properties of your element and any uses applications or anything interesting about your element.

Average Atomic Mass of an Element
Choose an element from the periodic table. (Each element may only be used once, so check to see which have been taken before you begin) Research and summarize how many different isotopes there are for your particular element. (For example, I believe Lithium only has 3) Explain and show how the average atomic mass for your element is calculated. HINT: this is VERY similar to the m&m activity we did last week.

Chemical Bonding
1. What are some general types of chemical bonds?
2. What is the major difference between an ionic and covalent bond?
3. Describe what causes atoms to bond to one another.

Chemical Reaction Types
Briefly research and summarize IN YOUR OWN WORDS these 4 major types of chemical reactions. What do they have in common? and, How are they different from one another? Synthesis, Decomposition, Single Displacement, Double Displacement

Distance - Time vs. Velocity - Time Graphs
A graph can be used to display a lot of different information. Imagine that you had to collect data during a running race and create 2 graphs. The first graph needs to compare the POSITION of the runner on the track to the time during the race. The second graph needs to compare the SPEED of the runner on the track to the time during the race. For your response, explain what your runner did during the race and what each of the graphs would look like. *Note: The only scenario you can not use is that the runner just stood still for the entire race. Again, explain what the runner physically DID and how each of the graphs would correspond.

Inertia & Friction
1. Research Newton's 1st law of motion often called "The Law of Inertia." Inertia is often referred to as the "laziness" of objects which is kind of odd because even objects that are moving have inertia. Explain in your own words what inertia is and why some objects have more than others. (there is more than one correct answer here)
2. Friction. Explain what it is as well as the only 2 accepted variables (covered in class) affecting the amount of friction between 2 surfaces in contact.

Mass vs. Weight
Regarding weight and mass, please explain: 1. How are they different (by definition). 2. The formula to solve for weight. 3. The units they are expressed in. 4. The tool used to measure each. 5. Which one changes when you go to the moon and why.

Newton's 2nd Law of Motion
1. What is Newton's 2nd law of motion? 2. Explain an everyday example of this law and the formula describing this law: F = ? as well as appropriate numbers and units with your example. 3. Previously, we've defined mass as "the amount of matter in an object." Physicists like to define mass as "an objects resistance to acceleration." Why does this definition make sense based on the 2nd law?

Falling Objects
Consider a bowling ball and a ping pong ball. 1. Explain what will happen when they are simultaneously dropped from a relatively low height here on earth. (Explain why you think this will happen while correctly incorporating the terms: gravity, acceleration, air resistance, and terminal velocity in your response) 2. Now explain what will happen when these same 2 objects are dropped from a much greater height here on earth. 3. Finally, explain how this scenario would differ on the moon where there is no atmosphere (i.e. a vacuum).

Projectile Motion
Assuming I provide you with the initial velocity of a projectile and it's trajectory angle, list by number, and explain the steps you would need to carry out in order to solve for the maximum projectile height and horizontal distance traveled. *Note: this is a good review, and your notes should help.
1. First I would need to do this because.....
2. next I would, because......
3. etc.

Forms of Energy
Energy comes in many forms, but in general, it may be classified as either potential energy or kinetic energy. Please:
1. Provide a definition for "energy"
2. Describe at least 1 example of potential energy
3. Describe at least 1 example of kinetic energy
4. Explain how the amount of energy in each of these situations could be determined.

Work and Power
1. Define Work and Power and include the formula for each as well as the units they are expressed in.
2. Explain a situation in which 20 J of work is performed to lift a 1 kg mass and then a 5 kg mass. (Don't forget to convert mass in (kg) to weight in (N))
3. Explain one or more ways it is possible for 2 different people to have the same amount of power while climbing a flight of stairs. (I can think of a few ways)

Actual vs. Ideal Mechanical Advantage
1. Briefly explain 2 ways that actual mechanical advantage (MA) differs from ideal mechanical advantage (IMA).
2. Explain how to solve for the Ideal mechanical advantage of a lever and why the Ideal mechanical advantage of a 2nd class lever is always greater than 1
As always, please answer in your own words. Thanks!

Mechanical Advantage of Various Machines
1. Solve for the I.M.A. of a 1st class lever having a 80 cm effort arm and 20 cm resistance arm.
2. Solve for the I.M.A. of an inclined plane having a 40 cm slope length and 10 cm slope height.
3. How does the I.M.A. compare and why?
4. The A.M.A. of the inclined plane would be less than the lever. Explain why.

Everyday Simple Machines
1. Choose a simple machine that you use in everyday life. (Note: each example may only be used once). i.e. if the first person to respond chooses a door knob. That can't be used again. And for my example I will use the door knob.

2. Explain what kind of simple machine your example is and how it works. For example, my door knob here at home is a wheel and axle simple machine and has an effort distance (knob radius) of 0.05 m and an axle radius of 0.01 m. By turning the knob, I gain a mechanical advantage because I apply a much lower effort force to the knob than I would need to apply to the axle inside. However, the trade off is that I need to apply that force over a much greater distance by turning the knob rather than the axle inside.

3. Calculate IMA. With these measurements I can calculate the IMA as 5. Therefore this door knob should theoretically reduce the necessary effort force 5 times. Of course, as always efficiency can not be 100%, and my actual mechanical advantage will be less than the IMA of 5 because of friction.

Wavelength, Frequency, and the Doppler Effect
1. Explain what the terms “wavelength” and “frequency” mean in your own words.
2. Briefly summarize the mathematical relationship between these 2 terms.
3. Summarize the term “Doppler Effect” in your own words and briefly explain how it is related to wavelength and frequency.
4. FInally, provide the URL to a reliable source you found during your research.

Wave Velocity, Frequency, and Wavelength
1. Research the Internet to find specific info on a wave type of your choice (*Note each example may only be used once, but there are many possibilities to choose from.) Just a few ideas include: earthquake primary waves, secondary waves, surface waves, ocean waves, tsunami waves, sound waves traveling through various media. (i.e. one person could use sound waves traveling through air on a hot day, and someone else on a cold day, while other students could use sound traveling through water, steel, wood, etc.) People may choose from the various types of radio waves, microwaves, infrared, ultraviolet, x-rays, gamma rays. People could even choose from the various colors (wavelengths) of visible light we can see. (i.e. red, orange, yellow, green, blue, indigo, violet, or anything in between)
2. State the type of wave you researched. Provide the following info: wavelength, frequency, and velocity of a typical wave of this type. *Note: these variables may change under different conditions, so just give us the average values or approximations. For example, on a windy day the frequency of waves on a lake may be higher than usual, so just explain yourself during your response.
3. Finally, include at least one URL to a reliable source you found during your research.

Wavelength and Frequency of Various EM Waves
Wavelength and corresponding frequency connection to objects from the size of mountains to atoms!
1. Choose and state a type of electromagnetic wave from this list: Radio, Microwave, Infrared, Visible Light, Ultraviolet, X-Ray, and Gamma Ray
2. Perform brief research to determine what the approximate wavelength and frequency if for such a wave
3. Also state something that has that approximate length, distance, diameter, etc. For example, the microwaves that we measured in class. What is something that has the length of 1 microwave? Or X-rays like those at the dentist's office. What is something that has that length? Again you can choose any type of EM wave from the list above. Lets make sure each wave type is represented in your responses. Thanks!