Class
28 Thursday,
11/15/18 Warm Up: The picture on the right shows how a chain can be used to pull a stuck car out of the mud. All that is required is a small sideways force applied to the center of the chain. Why does this work? Today:
Assignment Due Dates:


Class
27.5 Wednesday,
11/14/18 Warm Up: 1. How does Clifford Heath's water rocket simulator work? What can we learn from it? 2. How could you modify your spreadsheet to calculate: 1) "crashdown speed?" 2) Δx? Today:
Assignment Due Dates: These assignments are not optional. If you do not complete them, they will count as zeroes.


Class
27 Tuesday,
11/13/18
Warm Up: Two
boxes are initially at rest, relative to a the elevator in which they
sit.
When
a
person exerts a 200N rightward force over a time interval of 1 second,
the 20kg box moves a distance of 1.38m rightward.
What is the
10kg block's
x displacement
during that same time interval? Today:
Assignment Due Dates: These assignments are not optional. If you do not complete them, they will count as zeroes.


Class
26.5 Monday,
11/12/18 Warm Up: Suppose someone straps a stuffed koala to a rocket and then launches the koala and rocket directly upward. The rocket thrust lasts for 1 second and provides a constant force of 1,000N. During thrust, the average mass of the koala + engine + fuel + harness = 10kg. Ignoring air resistance, calculate the maximum height reached by the koala? For ease, you can assume that g=10m/s^{2}. Today:
Tomorrow: Work time to finish whatever you need to finish. Assignment Due Dates: These assignments are not optional. If you do not complete them, they will count as zeroes.


Class
26 Friday,
11/9/18 Warm Up: 1. What purpose does the formula in column Q serve? 2. Why don't the first several rows in column Q have formulas? Today:
Homework: 

Class
25.5 Thursday,
11/8/18 Warm Up: A 1kg mass is suspended by a string from the ceiling of a train car. The angle shown remains constant. 1. Describe the motions of the mass and the train car in qualitative terms. 2. How can we find the tension in the string? 3. How can we describe the motions of the mass and the train car in quantitative terms. Today:
Homework: 

Class
24.5 Tuesday,
11/6/18 Warm Up: Find the acceleration of each block and the tensions in the two strings. To make your work easier, use g=10m/s^{2} Assume that the pulleys and strings are massless and frictionless. Today:
Homework:


Class
24 Monday,
11/5/18 Warm Up: 1. How does NASA simulate weightlessness? 2. You are trying to transfer some drippy sauce across a dinner table using only a drippy spoon. The sauce needs to go from the pot to your plate without dripping. Touching only the spoon, how can you make this happen? 3. What would happen if you were standing on a bathroom scale in an elevator, and the elevator suddenly began to accelerate downward at 1g? 4. What is the source of the "butterflies in the stomach" when we fall? Today:
Homework:


Class
23.5 Friday,
11/2/18 Warm Up: The figure on the right shows Atwood's Machine. Write an equation for the acceleration of the masses in terms of m_{1}, m_{2}, and g. You may assume that the rope is massless and that there is no friction. Today:
Homework:


Class
23 Thursday,
11/1/18 Warm Up: If you need to stop a car quickly, why should you avoid locking the tires or skidding? Today:
Homework:


Class
22.5 Wednesday,
10/31/18 Warm Up: What if I put a large rock on my head, with a 2"x4" on top of the rock, and then I have someone hammer a large nail through the 2"x4"? Is this a good idea? Today:
Homework:


Class
22 Tuesday,
10/30/18 Warm Up: How many 100 psi water bottles would it take to launch a human? Today:
Homework:


Class
21.5 Monday,
10/29/18 Warm Up: 1. If a Wiffle® Ball has a mass of about 45g, what is the upper limit of the amount of force a thrower can apply to a Wiffle Ball during the throw? 2. Why is there a limit to how much force can be applied to a thrown Wiffle Ball? Today:
Online Textbook (OpenStax) Reading:
Homework:


Class
21 Friday,
10/26/18 Warm Up: Emergency clinic records of 132 cats that jumped from windows of buildings showed a 90% survival rate. The average drop was 5.5 floors.
Injuries increased with increasing heights up to 7 floors.
When cats fell from over 7 floors, they actually suffered from
“less injuries.”
1. When does a falling cat experience zero net force? 2. When is a falling cat a "freefalling" cat? 3. When does a falling cat experience maximum net force? Today:
Online Textbook (OpenStax) Reading:
Homework:


Class
20.5 Thursday,
10/25/18 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. Why does this method work? Today:
Online Textbook (OpenStax) Reading:
Homework:


Class 20
Wednesday,
10/24/18 Warm Up: 1. In a game of tugofwar, who pulls the hardest  the winners, the losers, or neither? Explain. 2. Why is the word pull in italics? Today:
Online Textbook (OpenStax) Reading:
Homework:


Class 19.5
Tuesday,
10/23/18 Warm Up: None Today:
Online Textbook (OpenStax) Reading:
Homework: Due on Wednesday:


Class 19
Monday,
10/22/18 Warm Up: None Today: 1) Watch this video. Make sure that you adjust the three volume controls: 1) computer volume, 2) YouTube volume, 3) Stereo Receiver volume
2) Work on Rockets:
3) Work on the homework (below) Online Textbook (OpenStax) Reading:
Homework: Due on Wednesday:


Class 18.5
Wednesday,
10/17/18 Warm Up: 1. How does a water rocket work? 2. Would a water rocket work better or worse in outer space? Explain. Today:
Online Textbook (OpenStax) Reading:
Homework:


Class 18
Tuesday,
10/16/18 Warm Up: Take a look at the 2D kinematics data relating to homework completion and test scores. What do you think? Means: 68% (A5/6), 84% (A7/8) Medians: 63% (A5/6), 88% (A7/8) Today:
Online Textbook (OpenStax) Reading:
Homework:


Class 17.5
Monday,
10/15/18 Warm Up: There is a heavy object suspended from the ceiling by a string. Another segment of the from the same roll of string is hanging 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:
Online Textbook (OpenStax) Reading:
Homework:


Class 17
Friday,
10/12/18 Warm Up: Test Today. No Warmup. Today: Chapter 3 Test Online Textbook (OpenStax) Reading:
Homework:


Class 16
Thursday,
10/11/18 Warm Up: 1. 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? 2. 1m/s = ____ mph. For tomorrow's test, memorize this or be able to calculate it based on a known conversion. Today:
Online Textbook (OpenStax) Reading:
Homework:


Class 15.5
Tuesday,
10/10/18 Warm Up: No Warmup Today:
Online Textbook (OpenStax) Reading: Homework:


Class 15
Tuesday,
10/8/18 Warm Up: No Warmup Today:
Online Textbook (OpenStax) Reading: Homework:


Class 14.5
Monday,
10/8/18 Warm Up: Will the blue hunter hit the monkey? Today:
Online Textbook (OpenStax) Reading: Homework:


Class 14
Friday,
10/5/18 Warm Up: A green hunter and a blue hunter point their guns directly at a fake orange monkey and then fire simultaneously. Just as the two hunters fire their guns, the fake monkey slips and freefalls from the treetop. [You may assume that this takes place in a vacuum on a flat earth.] 1. Where does each hunter's projectile end up, relative to the monkey? High, low, or in the monkey? 2. How would the result have been different if the monkey had stayed in position at the top of the tree? 3. Does the answer to either of these questions depend on the bullet velocities? Today:
Online Textbook (OpenStax) Reading: Homework: 

Class 13.5
Thursday,
10/4/18 Warm Up: Can you think of a more precise method of calibrating your launcher?  rather than shooting horizontally from a stool? What does precision mean? Today:
Online Textbook (OpenStax) Reading: Homework:


Class 13
Wednesday,
10/3/18 Warm Up: At the angle shown, can the projectile launcher hit the target? If not, how should the launcher be adjusted? Today:
Online Textbook (OpenStax) Reading: Homework: 

Class 12.5
Tuesday,
10/2/18 Warm Up: 1. The pilot of a small plane is navigating by pointing her plane directly southward while maintaining an air speed of 100m/s. If the plane has an actual eastward velocity of 50m/s, what is the velocity of the air that surrounds the plane? To eliminate some calculations, you can describe the wind velocity by providing its two component vectors. 2. If there were no windshield, and the propeller were momentarily removed, would the pilot feel air blowing from straight ahead or from some other direction? Today:
Online Textbook (OpenStax) Reading: Homework:


Class 12
Monday,
10/1/18 Warm Up: Sketch the component and resultant vectors for the following "river problems." 1. A paddler travels eastward at a rate of 3m/s. The paddler's heading is northeastward, and the paddler's speed in still water is 8m/s. What is the velocity of the water in which the paddler is paddling? 2. A quadcopter has a velocity of 20m/s westward. The wind is blowing southward at a rate of 10m/s. What are the quadcopter's airspeed and heading? 3. The driver of a golf cart on an aircraft carrier uses a compast to head northward. The cart's speedometer reads 10mph. The aircraft carrier's heading is eastward, and it's speed in still water is15mph. The ocean current is northwestward at a rate of 5mph. What is the actual velocity (relative to the Earth) of the golf cart? Today:
Online Textbook (OpenStax) Reading: Homework:


Class 11.5
Friday,
9/28/18 Warm Up: 1. How do you enter a formula in a spreadsheet (e.g. Google Sheets, or Excel)? 2. If you don't know how to do something in a spreadsheet, how can you find out how it's done? 3. How would you create a spreadsheet like the one on the right? Given a projectile's initial speed and launch angle, this spreadsheet calculates the x and y positions of the projectile at any given time. Today:
Coming up:
Online Textbook (OpenStax) Reading: Homework/Deadlines:


Class 11
Thursday,
9/27/18 Warm Up : Two canoe paddlers begin at the starting point in the diagram on the right. They paddle with a constant water speed. Paddler A maintains a westward heading while paddler B keeps the canoe pointed at the small island. 1. What is the difference between water speed and speed? 2. Which paddler is following a heading? 3. Describe the shape of the path followed by each paddler. 4. Now suppose we increase the scale of the problem, remove any current, and provide paddler A with a compass only at the beginning of her journey. She points her canoe westward, begins traveling in that direction, and maintains her speed in a perfectly straight path. Assuming that her path is perfectly straight, will she reach the island 1,000 miles away? Explain. 5. What does the previous question suggest about the assumptions of river problems in this class? 6. In this class, river problems will involve three velocities, a) the velocity of a medium (e.g. river water, or moving air) relative to the Earth, b) the speed of an object relative to the medium, and its direction (heading), relative to the Earth, and c) the velocity of the object relative to the Earth. Which of these three velocities will be the resultant vector in river problems? [It may be easier to think of these as the current's direction, the object's heading, and the object's actual path.] Today:
Coming up:
Online Textbook (OpenStax) Reading: Homework:


Classes 9.5 (Monday, 9/24), 10 (Tuesday, 9/25),
and 10.5 (Wednesday, 9/27) Work through these notes and problem sets. Please help one another. Also ask Mr. Chase for help. If you sign up for my Flex, he is in the same room (C211/212). Online Textbook (OpenStax) Reading:


Class
9 Friday,
9/21/18 Warm Up : 1. What are sine, cosine, and tangent? 2. Find the missing vector magnitudes on the right. Today:
Online Textbook (OpenStax) Reading: Homework:


Class
8.5 Thursday,
9/20/18 Warm Up: 1. Suppose the two vectors on the right represent two forces acting on the clam. In what direction will the clam accelerate? What will be the magnitude of the net force accelerating the clam in that direction? 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:
Online Textbook (OpenStax) Reading: Homework: 

Class
8 Wednesday,
9/19/18 Warm Up: No warmup today Today:
Online Textbook (OpenStax) Reading: Homework: 

Class
7.5 Tuesday,
9/18/18 Warm Up: 1. Propose an explanation for why this velocity graph is so scattered looking. 2. What five variables should you look for in kinematics problems? Today:
Homework:


Class
7 Monday,
9/17/18 Warm Up: 1. Eliud Kipchoge ran 26.22 miles in a time of 2:01:39. What was his average Δt, in minutes and seconds, for each mile? 2. Why is a marathon 26 miles, 385 yards? 3. Take a look at the formulas that you will be given on the test. Today:
Online Textbook (OpenStax) Reading: Homework:


Class
6.5 Friday,
9/14/18 Warm Up: Sometimes people celebrate special occasions by firing guns into the air. 1. Is this a dangerous way to celebrate? Why, or why not? 2. Why don't clouds fall out of the sky? Calculated terminal velocities of various spheres. Today:
Online Textbook (OpenStax) Reading: Homework: 

Class
6 Thursday,
9/13/18 Warm Up: 1. A race car is traveling counterclockwise around a circular track. The car's speedometer stays on exactly 100mph the whole time. Describe what happens to each of the following as the car makes one revolution around the track: a) the car's speed b) the car's velocity c) the car's acceleration. 2. All of the speed calculations in the screenshot on the right (blue) are slightly off, and the last speed calculation (red) is really, really off. Why?
Today:
Coming Up:
Online Textbook (OpenStax) Reading: Homework: 

Class
5.5 Wednesday,
9/12/18 Warm Up: Match each position vs. time graph with the correct velocity and acceleration graph. Today:
Coming Up:
Online Textbook (OpenStax) Reading: Homework:


Class
5 Tuesday,
9/11/18 Warm Up: A ball is launched directly upward from the Earth's surface. The ball returns to Earth and hits the ground after a time of 10 seconds. Assuming no air resistance and g≈10m/s^{2}, fill in the values in the diagram on the right. [Though the diagram appears to show horizontal motion, assume that there is none.] Today:
Online Textbook (OpenStax) Reading: Homework:


Class
4.5 Monday,
9/10/18 Warm Up: The symbol "g" usually represents the absolute value of the acceleration of gravity near Earth's surface (in the absence of air resistance). The approximate value of g is 9.8m/s^{2}. For the sake of simplicity, use g = 10m/s^{2} to complete the motion graphs for an object with v_{0} = 20m/s and y_{0} = 0m. [Ignore air resistance.] Today:
Tomorrow:
Online Textbook (OpenStax) Reading: Homework:


Class
4 Friday,
9/7/18 Warm Up: 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:
Online Textbook (OpenStax) Reading: Homework:


Class
3.5 Thursday,
9/6/18 Warm Up: 1. How does the Amazing Water and Sound Experiment work? 2. Answer to yesterday's warmup#3?. Today:
Online Textbook (OpenStax) Reading: Homework: 

Class
3 Wednesday,
9/5/18 Warm Up: 1. Assuming that the man in the picture is 2m tall, and the frame rate of the camera was 30 frames per second, what were the approximate maximum and minimum speeds of the object? 2. Based on your answers, do you think the assumption of 30 frames per second was too loww, too high, or about right? 3. If you could travel in time, and you found yourself in the infinite loop of acceleration changes shown below... a) what might your velocity and position graphs look like?, and b) would you ever find yourself in the same location as another past self? If so, show how this could occur.
Today:
Online Textbook (OpenStax) Reading: Homework:


Class
2.5 Tuesday,
9/4/18 Warm Up: A runner sprints exactly 100m, rests for a moment, and then slowly follows the same path back to the starting line. This entire trip takes 200s. For the questions below, consider the runner's entire round trip.1. What distance did the runner travel? 2. What was the runner's displacement? 3. What was the runner's average velocity? 4. What was the runner's average speed? Today:
Handouts: Online Textbook (OpenStax) Reading: Homework: 

Class
2 Friday,
8/31/18 Warm Up: Use the velocity vs time graph on the right to sketch the shape of a corresponding position vs time graph. [Hint: positive velocity corresponds to movement away from a motion sensor.] Today:
Handouts: Online Textbook (OpenStax) Reading: Homework:


Class
1.5 Thursday,
8/30/18 Warm Up: For each letter, describe what is happening to the person's speed and direction during the 10 seconds represented on the graph. Today:
Handouts: Online Textbook (OpenStax) Reading: Homework:


Class
1: Wednesday,
8/29/18 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:
Handouts: Online Textbook (OpenStax) Reading: Homework:
