Class
41:
Tuesday
11/10/2020 Warm Up: Rocket Launch -- No Warm-up -- See you all Term 3!
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Class
40:
Monday
11/9/2020 Warm Up: Test today -- No warm-up
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Class
39:
Friday
11/6/2020 Warm Up: Rocket Launch -- No warm-up
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Class
38:
Thursday
11/5/2020 Warm Up: Test today -- No warm-up, no Meet
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Class
38:
Wednesday
11/4/2020 Warm Up: We have really only dealt with 4 different kinds of forces. Can you name them?
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Class
37:
Monday
11/2/2020 Warm Up: Test today -- No warm-up, no Meet
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Class
36:
Thursday
10/29/2020 Warm Up: 1. Starting from rest1, a car accelerates2 to its maximum velocity, maintains that velocity3 for a few seconds, and then brakes as quickly as possible4, finally returning to rest. Show how the net force and the individual forces acting on the car change over time. Use labeled arrows to show all of the forces (and the net force) acting on the car during each of these numbered time periods.
2. A 50kg rower accelerates at a rate of -1m/s2 due to her application of a 100N force to the oars. Calculate and show all of the forces acting on the rower. [For further fun, you might draw the forces acting on one oar, or the forces acting on the boat itself.]
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Class
35:
Thursday
10/29/2020 Warm Up: If you need to stop a car quickly, why should you avoid locking the tires and skidding? What type of friction stops a car?
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Class
34:
Wednesday
10/28/2020 Warm Up: A person pushes a box with a force of 21N, as shown. This causes the two boxes to accelerate. If there is no friction between the boxes and their sliding surface... 1. What is the "contact force" between the two boxes? 2. What are all of the individual forces and net forces that are acting on each box?
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Class
33:
Tuesday
10/27/2020 Warm Up: No warm-up today, to give retakers a little more time.
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Class
32:
Monday
10/26/2020 Warm Up: A parachuter steps out of a plane. The total mass of the parachuter and gear is 100kg. After falling for a while, the parachuter reaches a terminal velocity of -55m/s. A short time later, the parachuter pulls the chute cord and reaches a new terminal velocity of -3m/s. From that point in time, the parachuter continues to drift to the ground. Fill out the missing data in this table...
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Class
31:
Friday
10/23/2020 Warm Up: According to this article, 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. What's going on? 2. What's the rule for deciding whether to use "less" or "fewer?" Which applies here? 3. When does a falling cat experience zero net force? 4. When is a falling cat a "free-falling" cat? 5. When does a falling cat experience maximum net force?
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Class
30:
Thursday
10/22/2020 Warm Up: 1. Which can you throw with more force, a Wiffle Ball® (0.045kg), a baseball (0.145kg), or a bowling ball (6.3kg)? Or is there no difference? Explain your thinking. 2. What limits the amount of force that you can apply when you throw a light object, like a Wiffle Ball, or a feather? Interesting Link: article about the fastest pitch ever thrown
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Class
29:
Wednesday
10/21/2020 Warm Up: Draw (or imagine) a diagram showing all of the forces that are acting on a person who is walking to the left. Label the forces.
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Class
28:
Tuesday
10/20/2020 Warm Up: 1. 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? 2. What are some words that you can use to interrupt Mr. Stapleton if you're at home on the Google Meet?
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Class
27:
Monday
10/19/2020 Warm Up: 1. Explain how a nordic skier can ski forward on level ground with parallel skis and without using poles. 2. Can this be done with downhill skis? Explain.
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Class
26:
Friday
10/16/2020 Warm Up: 1. 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? 2. Newton's 2nd Law says Fnet = ma. I have emphasized that ma equals the net force acting on an object. In light of this, is it really okay to calcultate a 1kg brick's weight using the method on the right?
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Class
25:
Thursday
10/15/2020 Warm Up: None
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Wednesday 10/13/2020 -- No Google Meet today. Mr. Stapleton is proctoring the PSAT. |
Class
24:
Tuesday
10/13/2020 Warm Up: None
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Class
23:
Thursday
10/8/2020 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?
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Class
22:
Wednesday
10/7/2020 Warm Up: 1. 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? 2. 1m/s = ____ mph. For next week's test, memorize this or be able to calculate it based on a known conversion. 3. Discuss #2 and 3 from yesterday's warm-up???
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Class
21:
Tuesday
10/6/2020 Warm Up: 1. How would you solve this problem?
A forklift on an aircraft carrier is traveling with a velocity of 4m/s in a direction 32 degrees west of North, relative to the Earth. If the aircraft carrier's velocity is 6m/s, in a direction 10 degrees east of North, what are the forklift's heading and speedometer reading? Video of solution 2. Would this strategy work for a simple, orthogonal river problem? 3. For any projectile problem, which kinematics formulas apply to the y dimension? Which ones apply to the x dimension?
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Class
20:
Monday
10/5/2020 Warm Up: How would you solve this problem?
A boat has a heading that is 25 degrees South of West, and its water speed is 14m/s. The boat is traveling in a river with a current that is flowing at a rate of 5m/s in a direction 65 degrees East of South. What is the boat's velocity, relative to the Earth?
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Class
19:
Friday
10/2/2020 Warm Up: 1. Two of the vectors A, B, and C add up to the third vector. Which is the resultant? 2. Point D lies on the curvy path followed by an object. How would we properly draw the object's V, Vx, and Vy at point D?
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Class
18:
Thursday
10/1/2020 Warm Up: 1. List all of the basic formulas that will be provided (if you choose to accept them) on the next test. 2. Drawing from that list of formulas, derive a specific formula for calculating the initial velocity (vo) of a projectile that is launched horizontally from a height (h) above the floor and which travels a horizontal distance x before landing on the floor.
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Class
17:
Wednesday
9/30/2020 Warm Up: 1. Based on the existing pattern, what should number should appear in the 7th row of column C? 2. If we wanted to continue that pattern quickly and easily, how could we set up a spreadsheet to do it?
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Class
16:
Tuesday
9/29/2020 Warm Up: An airplane flying horizontally with a ground speed of 120 m/s releases a bomb from a height of 4,800 meters. If the bomb is not affected by air resistance, how far ahead of the target (in the x dimension) should the bomb be released?
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Class
15:
Monday
9/28/2020 Warm Up: A green hunter in a treetop points a gun at a fake orange monkey and fires. Just as the hunters fires the gun, the fake monkey slips and freefalls from the treetop. Assuming that the monkey and the bullet to do not hit any obstacles besides one another, does the monkey get shot? Explain. [You may also assume that the bullet does not encounter any air resistance.]
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Class
14:
Friday!!!
9/25/2020 Warm Up: 1. What do "air speed" and "speed in still water" mean? 2. What is a "heading?"
Identify the component and resultant vectors for the following "river problems." Then sketch them using head-to-tail vector addition. 3. A boat travels eastward at a rate of 3m/s. The boat's heading is northeastward, and the boat's speed in still water is 8m/s. What is the velocity of the water in which the paddler is paddling? 4. 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? 5. The driver of a golf cart on an aircraft carrier uses a compass to head northward. The cart's speedometer reads 10mph. The aircraft carrier's heading is eastward, and its 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?
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Class
13:
Thursday,
9/24/2020 No Warm-up
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Class
12:
Wednesday,
9/23/2020 No Warm-up
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Class
11:
Tuesday,
9/22/2020 No Warm-up
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Class
10:
Monday,
9/21/2020 Warm Up: 1. The position vs. time graph on the right is intended to show two intervals of constant acceleration. Find the approximate values of those two accelerations. 2. If we have time, sketch an acceleration vs. time graph of a pedestrian's left foot.
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Class
9
Friday,
9/18/2020 Warm Up: Mr. Chase pointed out that there are 9 types of motion. This is based on the fact that Velocity can be +, -, or 0, and acceleration can also be +, -, or 0. This video of a spring-bound object oscillating on an air track demonstrates 8 out of these 9 types of motion. 1. Identify where in the video each of those 8 types of motion occurs. 2. Which type of motion is not demonstrated?
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Class
8
Thursday,
9/17/2020 Warm Up: What would the graphs look like if you graphed acceleration for these event #2? We are only doing #2 together, but try the rest if you want. My answers -- Note that my total areas under the curve for 1 and 2 should be zero, but they're not. I should re-do them some day. 1. A PE student runs from one end of the gym to the other and back (wall to wall) as fast as possible. 2. A basketball is dropped from high above a gym floor and bounces back up until its velocity reaches zero. 3. A skydiver steps out of a plane, begins to fall, opens a parachute, falls some more, and hits the ground. [Assume all motion is vertical.] 4. How would you use dimensional analysis to convert 4m/s to mph? Mathematically speaking, why does dimensional analysis work?
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Class
7
Wednesday,
9/16/2020 Warm Up: Match each position vs. time graph with the correct velocity and acceleration graph.
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Class
6 Tuesday,
9/15/2020 Warm Up: Sketch a graph of acceleration vs. time for a suction cup Nerf dart that is shot at a wall. Start your graph just before the dart begins to move, and end it just after the dart stops.
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Class
5 Monday,
9/14/2020 Warm Up: In the physics world, an object is in "free-fall" as long as gravity is the only force acting on that object. The object may free-fall upward or downward. Near the Earth's surface, the acceleration of free-falling objects due to gravity is approximately -9.8m/s2. Consider the case of this ball. At t = 0s, the ball is free-falling directly upward 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/s2 instead of g = 9.8m/s2]
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Class
4 Friday!!!!,
9/11/2020 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.
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Class
3 Thursday,
9/10/2020 Warm Up: Use the velocity vs time graph on the right to sketch: a position vs. time graph.
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Class
2 Wednesday,
9/9/2020 Warm Up: For each letter, describe what is happening to the person's speed and direction during the 10 seconds represented on the graph.
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Class
1: Tuesday,
9/8/2020 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:
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