Class
28: Monday,
11/27/23 Warm Up: Get together with your group and make a copy of the "[your names]Water Rocket Flight Model" spreadsheet in Google Classroom. We're going to populate it together.
Today:
Homework:

Class
27.5: Friday 11/17/23 Warm Up: To make this velocity graph (top), I pasted data from Vernier Video Analysis into Sheets and graphed Yvelocity vs. time. Then I used the basic acceleration formula to calculate accelerations from the velocity and time data. I graphed those and got the acceleration graph on the left. Then I used Elena's clever trick and created the far superior acceleration graph on the right. How did I do it?
Today:
Homework:

Class
27: Thursday 11/16/23 Warm Up: Let's set up your spreadsheet together, so that it works like this one. Today:
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Class
26.5: Wednesday 11/15/23 Warm Up: How many water bottles are used to launch this game show contestant? Is this for real? Could we launch a student this high? Today:
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Class
26: Tuesday 11/14/23 Warm Up: The drawing on the right shows important times that can be used to model the rocket's flight. I will record a closeup video of the thrust period and the landing. Others will video the entire flight from afar.
Today:
Homework:

Class
25.5: Monday 11/13/23 Warm Up: What's the best amount of water to put in a water rocket? [Find out, according to Clifford Heath.] How does the amount of water affect force and overall change in velocity? 1. What happens if you don't add any water? 2. What happens if you completely fill the rocket with water? Today:
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Class
25: Friday 11/10/23 Warm Up: None Today:
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Class
24.5: Thursday 11/9/23 Warm Up: The diagram on the right shows a 2liter bottle water rocket. Mass has been added to the tip of the rocket's nose cone, and fins have been added to the back (bottom). The nose cone sits loosely on a platform that is hidden beneath the nose cone's flange. The nose cone and pressure chamber are not fused together, but they are connected by a string, which also connects to the parachute. Video of one rocket another video 1. What makes the rocket move upward? 2. Why do fins need to be added to the back of the rocket? How does this work? 3. Why does mass needed to be added to the front of the rocket? How does this work? 4. Aside from stability, what other reason is there for adding mass to the rocket? 5. What's the purpose for the flange at the bottom of the nose cone?
Today:
Homework:

Class
24: Wednesday 11/8/23 Warm Up: 1. How fast does chalk fall? Is it faster than a cat?... My spreadsheet answer 2. Sometimes people celebrate special occasions by firing guns into the air. Is this safe? 3. Why don't clouds fall out of the sky? Calculated terminal velocities of various spheres.
Today:
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Class
23.5: Tuesday 11/7/23 Warm Up: Provide a quantitative explanation for what is going on in this situation.
Both A and B are initially motionless, and each has a weight of 6N. You apply an increasing leftward force to B, and both objects begin to move when your applied force reaches 3N (leftward). If you do not exceed 3N, and you stop applying force, the blocks continue to move at a constant speed.
Today:
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Class
23: Monday 11/6/23 Warm Up: Given the coefficient of friction between the top mass and the table top, find the masses' acceleration. The pulleys and strings are massless and frictionless. [Hint: treat all of the masses as one object and follow the usual recommended steps.]
Today:
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Class
22.5: Thursday,
11/2/23 Warm Up: On level ground, Tim begins sliding with a velocity of 6m/s. If Tim's slide lasts for 2 seconds, what is the coefficient of kinetic friction between Tim and the slide?
Today:
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Class
22: Wednesday,
11/1/23 Warm Up: How many Newton's 3rd Law action/reaction pairs of forces can you identify in this situation... Someone is standing still on a bathroom scale in a motionless elevator. Today:
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Class
21.5: Tuesday,
10/31/23 Warm Up: One way to find the center of mass (a.k.a. balance point) of a stick is to support it with two hands and then slowly move those two hands together until they meet under the stick's center of mass. How does this method work?
Today:
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Class
21: Monday,
10/30/23 Warm Up: None
Today:
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Class
20.5: Friday,
10/27/23 Warm Up: The rower in the photo has a mass of 50kg and a leftward acceleration of 1m/s^{2}. She is pulling against the oars with a total force of 100N. Sketch a diagram showing all of the forces acting on the rower. Find all of the forces' magnitudes.
Today:
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Class
20: Thursday,
10/26/23 Warm Up: Is it literally possible to "pull yourself up by your own bootstraps?" Explain.
Today:
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Class
19.5: Wednesday,
10/25/23 Warm Up: I have a length of treated 4"x4" lumber, some large nails, a hammer, and a large rock. How will it feel if I put the rock on my head and then have someone pound nails into the wood on top of the rock?
Today:
Homework:

Class
19: Tuesday,
10/24/23 Warm Up: A common occurrence in physics problems is someone standing on a bathroom scale inside an elevator. 1. Sketch vectors representing all of the forces (pushes or pulls) that are acting on the person in the elevator. 2. Write Newton's 2nd law (applied to the person) and plug in any values that you can. 3. Write an equation for net force as the vector sum of all of the forces acting on the person. 4. Set those two expressions of net force (net force as m*a and net force as the vector sum of forces) equal to one another and solve. Figure out what's "going on."
Today:
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Class
18.5: Monday,
10/23/23 Warm Up: It is possible to remove a sheet paper from under a dry erase pen without touching or tipping the pen. How can one do this without tipping the pen? Why does the pen usually fall? What kind of pen would work better?
Today:
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Class
18: Friday,
10/20/23 Warm Up: None Today:
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Class
17.5: Thursday,
10/19/23 Warm Up: How does NASA simulate weightlessness?
Today:
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Class
17: Wednesday,
10/18/23 Warm Up: What will happen if I poke a knife through a potato, hold both objects in the air with the knife pointing downward, and then hammer the butt of the knife into the potato? Why? What if it's an apple, because I didn't have potatoes?
Today:
Homework:

Class
16.5: Tuesday,
10/17/23 Warm Up: There is a heavy object suspended from the ceiling by a string. Another segment of the same string is hanging downward from the object. I am going to pull on the bottom string until one of the two strings breaks. Which string is going to break first? Why?
Today:
Homework:

Class
16: Monday,
10/16/23 Warm Up: None Today:
Homework:

Class
15.5: Friday,
10/13/23 Warm Up: Consider these things...  If you don't finish your plans in class, how are you going to know what the muzzle height will be when you tilt your launcher to a particular angle?  Plan your second shot. What if your first shot is 0.5m short? Or not high enough, and it hits an obstacle? By how much will you adjust your launcher setting for every 0.5m of error? What do you need to do to make an adjustment if you hit an obstacle?  How are you going to support and aim your launcher?  what happens if your rubber bands break?  what if your calibrations seem inexplicably wrong (all of the sudden)?  is there any other contingency that you can plan out ahead of time?
Today:
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Class
15: Thursday,
10/12/23 Warm Up: This diagram represents freefall. 1. If you were writing directions explaining how to draw Vx, Vy, and V for each of the three points in the diagram, what would you write? 2. How does speed change during the flight? 3. How does velocity change during the flight? Today:
Tomorrow:
Monday: Here's a short video explaining the launching rotation process
Homework:

Class
14.5: Wednesday,
10/11/23 Warm Up: None
Today:
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Class
14: Tuesday,
10/10/23 Warm Up: 1. Use your spreadsheet to solve this. Write your answer on a sheet of paper so that I can see it. What is the initial velocity of projectile that is launched horizontally from a height of 0.9m, if the projectile travels 2.5m before hitting the floor? 2. Can you think of some experiments that you could perform in order to answer the question, "how does the launch angle of one of our projectile launchers affect the initial velocity of the projectile?" Today:
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Class
13.5: Thursday,
10/5/23 Warm Up: Suppose you calibrated your launcher using the horizontal method, and you determined that a launcher setting of 7 produces an initial speed of 5.6m/s. Later on, you need to launch your projectile with an initial speed of 5.6m/s, but the launch angle needs to be 45 degrees. If you launched with a setting of 7 at a 45 degree angle, you probably won't hit the target. What is the main source of error? How can you compensate for this error? Today:
Homework:

Class
13: Wednesday,
10/4/23 Warm Up: Suppose you are calibrating your launcher by launching horizontally. The bottom of your projectile has a height of 0.82m when it leaves your launcher. You could automate the Vo calculations (in m/s) by setting up the spreadsheet cells on the right. [note: 1ft = 0.305m] 1. What formula should go in the yellow cell? 2. What formula should go in the green cell?
Today:
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Class
12.5: Tuesday,
10/3/23 Warm Up: None  hand in your homework with your name on it. I'm going to check a few answers, keeping the owner anonymous (unless they're correct).
Today:
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Class
12: Monday,
10/2/23 Warm Up: Let's use My Spreadsheet to solve this problem... Suppose we can launch a projectile from any position within a 0.5m vertical window above the "launch point," which is 0.75m above the floor. 1. What initial angle and speed should we use to hit the target while avoiding the obstacles and the ceiling? 2. How far should we stretch the launcher bands?
Today:
Homework:

Class 11.5:
Friday,
9/29/23 Warm Up: 1. On your chromebook, open your spreadsheet and see if you can make a graph that looks like this one (Y position vs X Position). 2. Next make a copy of your graph and "move it to its own sheet."
Today:
Homework: Mr. Pennington's test problems #46 on p.14 of the Unit 2 Packet (PDF) Unit 2 Answer Key 
Class 11:
Thursday,
9/28/23 Warm Up: An olympic athlete throws a javelin at an angle of 34 degrees, with respect to the ground. The release point of the javelin is 1.3m above the ground. The javelin travels a horizontal distance of 90 meters and lands after a flight lasting 3.7 seconds. 1. At what angle is the javelin sticking out of the ground at its point of impact? 2. It turns out that the field is not level. How much higher or lower is the field at the point of impact, compared to the field at the point of release? Today:
Homework:

Class 10.5:
Wednesday,
9/27/23 Warm Up: The diagram on the right shows the symmetric trajectory of a freefalling projectile. Sketch the diagram. 1. What does freefalling mean? 2. At each labeled point (A, B, and D) show/label the projectile's overall velocity vector (v), x velocity vector (v_{x}), and y velocity vector (v_{y}).
Today:
Homework:

Class 10: Tuesday,
9/26/23 Warm Up: None (so there's time for the retake)
Today:
Homework: See class #9.5, below. 
Class
9.5: Monday,
9/25/23 Warm Up: Here are a couple of 2D motion simulations... What's the ideal angle for launching a projectile, if you want it to travel the greatest horizontal distance? Why is that angle best? Today:
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Class
9: Friday,
9/22/23 Warm Up: Let's explore the "classic river problem" using some helpful tables (vector addition and kinematics)! Here's a review of the problem... An 80m wide river flows due south at a rate of 2m/s. Jane and Bob are on the west bank of the river, and they want to travel to a point on the opposite bank, directly eastward from their starting point. In still water, Jane and Bob can paddle a canoe at a speed of 3m/s. On land, each of them can travel at a rate of 4m/s...
Whose plan will get them there fastest?
Today:
Homework:

Class
8.5: Thursday,
9/21/23 Warm Up: Sketch a headtotail diagram for each of the following. Two "component" vectors should add up to the "resultant." The trickiest part is identifying the resultant.
2. A river's 3mph current flows in a direction 15 degrees West of North. A swimmer, whose speed in still water is 2m/s, swims across the river with a heading 35 degrees South of West. What is the swimmer's velocity, relative to the Earth? 3. A superhero steward on an airplane is traveling in a direction 10 degrees East of South, and their speed is 580mph. The plane's velocity is 460mph in a direction 5 degrees West of South. What is the steward's heading and their "speed on a still plane?"
Sketches and answers:  I got rid of number 1. Just ignore solution #1.
Today:
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Class
8: Wednesday,
9/20/23 Warm Up: 1. Find the missing values of Vx, Vy, and theta. 2. In the diagram on the right, should Vy be 7m/s, instead of 7m/s? Today:
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Class
7.5: Tuesday,
9/19/23 Warm Up: 1. Suppose the two vectors on the right represent two forces acting on the clam. In what direction will the clam accelerate? How will that acceleration compare to the accelerations we would observe if each force were acting alone? 2. The diagram on the right shows a top view of a train car that is moving at a rate of 2m/s. You are in the car. In which direction and how fast should you walk in order to have the intended velocity shown on the right. Today: Homework:

Class
7: Monday,
9/18/23 Warm Up: None Today:
Homework: None 
Class
6.5: Friday,
9/15/23 Warm Up: Velocity and Acceleration Combinations Practice Quiz. Use this link to take the quiz. Today:
Homework:

Class
6: Thursday,
9/14/23 Warm Up: Consider the X dimension motion of a pendulum that is continually swinging back and forth (left to right and back). 1. Draw quick sketches of velocity and acceleration graphs for a time period beginning at the leftmost point in the swing and continuing through one full cycle (over to the right and back). For the acceleration graph, the only expectation is that the sign (+,, or 0) is correct at any given moment. 2. Identify points in its motion where it demonstrates some of the "9 types of motion." Which types of motion does it not demonstrate?
Today:
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Class
5.5: Wednesday,
9/13/23 Warm Up: On Moon A, freefall acceleration has 1/6 the magnitude of freefall acceleration on Planet B. If an object is thrown vertically upward on Moon A, how will its vertical distance traveled compare with the vertical distance it would travel on Planet B?
This is a common type of physics problem. In this type of problem, you're given a proportional change in some independent variable (e.g. "if we double the object's acceleration"), and you're asked to find the proportional change in some dependent variable (e.g. "by what factor will the object's displacement be multiplied?"). 1. What's a good strategy for this type of problem? 2. What's the answer to this one? Higher resolution drop of feather and bowling ball Today:
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Class
5: Tuesday,
9/12/23 Warm Up: 1. Suppose students enter our school at a rate of 54 pounds/sec (pounds of student). After they enter, they lie down, headtotoe, forming a line whose length is the sum of their heights. Since an average 16 year old student's weight:height ratio is about 2.07 lb/in (and assuming these are all average students with that ratio), how many days will it take them to form a line 3 miles long? Video 2. How does dimensional analysis work? On what basic mathematical premise is it based? 3. This problem (#1) is fine for dimensional analysis practice, but it's not actually solvable given the information provided. Explain. Today:
Homework:

Class
4.5: Monday,
9/11/23 Warm Up: Consider the case of this ball. At t = 0s, the ball is freefalling directly upward at a height o 10m, with a speed of 20m/s. Sketch graphs of the ball's position, velocity, and acceleration (vs. time) over the next 4 seconds. [For simplicity, use g =10m/s^{2} instead of g = 9.8m/s^{2}] Today:
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Class
4: Friday,
9/8/23 Warm Up: When you're preparing for a test, it is important to understand the scope of what you are expected to be able to do. For your first physics test, the scope of kinematics problems is defined by the variables and formulas on the right*. 1. Use some of the variables to create a physics problem that you could use to test yourself in preparation for the real test. 2. Can you anticipate how I might go about writing several problems for the test? *There are a few "formulas" that I did not list, because you are expected to internalize them  for instance. Today:
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Class
3.5: Thursday,
9/7/23 Warm Up: Suppose a dart, starting from rest, is thrown from left to right across a room, finally embedding in a dart board. Sketch a graph of the dart's x acceleration (horizontal acceleration only) from the time it begins to move to the time at which it stops.
Today:
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Class
3: Wednesday,
9/6/23 Warm Up: Mr. Chase once said that there are 9 types of motion... 1. For letter a, on the right, describe what an object could be doing in order to have both positive velocity and positive acceleration. 2. Do the same for the rest of the letters.
Today:
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Class
2.5: Tuesday,
9/5/23 Warm Up: Match each position vs. time graph with the correct velocity and acceleration graph.Today:
Links: Homework:

Class
2: Friday,
9/1/23 Warm Up: 1. Use the velocity vs time graph on the right to sketch a corresponding position vs time graph. [Assume that motion away from the sensor is positive, and motion toward the sensor is negative.] 2. Where in the graphs is there acceleration (any change in velocity)? Today:
Links: Homework:

Class 1.5:
Thursday,
8/31/23 Warm Up: Suppose you're involved in a 2 lap race. If you want your overall average speed to be twice as fast as your speed for the first lap, how much faster do you have to go during the 2nd lap? [To calculate average speed you can use rate = distance / time] Solution  don't peek! Today:
Links: Homework:

Class
1: Wednesday,
8/30/23 (short class today  A5/6 ends at 12:40, A7/8 at 2:15) Physics 200: Mr. Stapleton Warm Up: Spin one of the "sprotating cylinders" by pressing one end until it squirts out from under your finger. Try pressing the other end. When the cylinder is spinning, why do you only see the symbol that you press? Today:
Links: Online Textbook Reading: Homework: Finish the questions on page 5 of the packet (assuming that you haven't already finished them). 