Class
21
Friday,
3/5/21 Warm Up: A spring hangs from the ceiling. When a mass m is attached to the end of the spring, released from that position, and allowed to come to rest, the end of the spring is a distance x lower than before the weight was added.
1. Which method below will not work for finding the spring constant k? Why?
2. Sketch a graph of PE, KE, and OE versus time. Today:
Homework:

Class
20
Tbursday,
3/4/21 Warm Up: None  to save time for test retakes Today:
Homework:

Class
19
Wednesday,
3/3/21 Warm Up: Bonus question due on Friday (email or on paper)  Assuming that mechanical energy is conserved, at precisely what minimum speed must a car enter a 10m radius looptheloop in order to not lose contact with the road surface? Today:
Homework:

Class
18
Tuesday,
3/2/21 Warm Up: None  to save time for test retake Today:
Homework:

Class
17
Monday,
3/1/21 Warm Up: 1. Can you guess what the "sisyphus train" does? 2. How did it get that nickname? 3. In the context of physics energy problems, some forces are called conservative, and others are referred to as nonconservative. Can you guess the difference between the two? (Probably not)
Today:
Homework:

Class
16
Friday,
2/19/21 Warm Up: None Today:

Class
15
Thursday,
2/18/21 Warm Up: None Today:

Class
14
Wednesday,
2/17/21
Warm Up: The graphs above show the net force applied to an object as it moves to various positions, relative to its origin. 1. Calculate the amount of work represented by each graph. 2. Can you describe the overall change in kinetic energy in each of these scenarios? Explain. 3. Sketch your own graph of net force vs position for an elevator that travels from the 1st to 2nd floor. Assume that the elevator starts and ends at rest. Calculate the total work for the motion that you graphed. 4. In number 3, it takes energy to lift an elevator. Where does the energy go? 5. How are these force vs. distance graphs similar to graphs of acceleration vs. time? 6. Which of the graphs below is possible?
Today:

Class
13 Tuesday,
2/16/21 Warm Up: Do you know how to make a cloud in a 2liter bottle, using water and a small amount of smoke? Can you explain the process in terms of work and energy?
Today:

Class
12 Monday,
2/15/21 Warm Up: How are "gforces" dangerous to pilots? What can they do to mitigate the danger? Today: Get the Unit 6 Packet  Work and Energy. Begin the new unit. If we don't get through #6 on page 2 of the packet, we will finish the notes on Wednesday.
Practice: Complete "Work and Energy Practice Problems" #15 on pages 34 of the Unit 6 Packet. Some answers/solutions Solutions to 3 and 4 
Class
11 Friday,
2/12/21 Warm Up: 1. Suppose a 1,000kg car is traveling through a looptheloop at a constant speed. The radius of the looptheloop is 5m, and the car is traveling at the slowest speed that will allow its wheels to remain in contact with the "road" at the top of the loop. Calculate the car's velocity. Then identify and calculate all of the individual forces acting on the car at each drawn location. 2. Can a human run through a looptheloop?
Today:
Homework:

Class
10 Thursday,
2/11/21 Warm Up: 0. Where are all of the videos that I have recorded during class? 1. What is a geosynchronous satellite? 2. What's the difference between a geosynchronous orbit and a geostationary orbit? 3. What is a space elevator? 4. Does raising an elevator require a force greater than the elevator's weight? Explain. Today:
Practice: 20192020 Test: Circular Motion, Gravity, and Kepler's Laws Answers/Solutions 
Class
9 Wednesday,
2/10/21 Warm Up: From 20162017 EPS 200... The Sun, Earth, and Moon are continually spaghettifying one another. On Earth, we see the effects of this spaghettification in the form of tides. 1. What causes spaghettification? 2. How much gravitational force do the Sun and Moon each exert on 1,000,000 pounds of water on the Earth's surface? How much space would that much water occupy? 3. Even if there were no water on Earth, there would still be tides, just as there are tides on the Moon. Describe these tides. 4. Why do we always see the same side of the moon? 5. Is the Earth's 24 hour rotational period speeding up or slowing down over time? Answer Today:
Practice: Gravity/Circles Practice Test  201819 Test Solutions to 1819 Gravity/Circles Test Video explaining solutions (These are my solutions that I used to grade the tests; the solutions are not necessarily written so that they are easy to follow.) 
Class
8 Tuesday,
2/9/21 Warm Up: According to the diagram on the right... 1. At what approximate date is the Earth orbiting with the fastest speed? When is it orbiting the slowest? 2. Rank our seasons in order of length. Answer 3. What's this, and why am I showing it to you? Today: Probably a short class today. We're going over the last new thing in this unit  Kepler's 3rd Law.
Practice: Packet P. 6, # 14, and 15. 
Class
7 Monday,
2/8/21 Warm Up: None  but we will have a short Google Meet Today:

Class
6 Friday, 2/5/21 Warm Up: None  but we will have a short Google Meet Today:

Class
5 Thursday, 2/4/21 Warm Up: 1. Approximately how fast is the space station rotating in 2001  A Space Odyssey? 2. If the jogger turned around and jogged in the opposite direction, how might he feel different? 3. How does NASA simulate weightlessness? Are astronauts and candles weightless when they are in the international space station, orbiting Earth? What word best sums up their motion?
Today:
Reading (optional):
Homework: .

Class
4:
Wednesday
2/3/21 Warm Up: A ball is tied to a string, and someone is holding the string, swinging the ball in circles at a constant speed of 10m/s. 1. Define acceleration. 2. What is the direction of the ball's acceleration? 3. How is the ball's acceleration related to its speed? 4. How is the ball's acceleration related to the length of the string?

Class
3:
Monday
2/1/21 Warm Up: A waiter is delivering a chunk of bone, basted in synovial fluid, to some dinner guests. Touching only the serving tray (also made of bone), the waiter must deliver the dinner bone to the guests, and place it carefully on their table. Assuming the guests' table is to our left in the picture, describe what the waiter would need to do in order to make this happen?

Class
2:
Friday
1/29/2021 Warm Up: 1. Cheryl wants to use some string and a nail to hang a treasured portrait of greatgreatgrandfather Ernesto as a young man. The portrait is rather heavy. Rank the three configurations on the right according to their risk of exceeding the breaking strength of the string. Assume that all pictures are supported by two strands of string. 2. What do static equilibrium and dynamic equilibrium mean, as they relate to physics problems?

Class
1:
Thursday
1/28/2021 Warm Up: A 1kg mass is suspended by a string from the ceiling of a fullyenclosed train car. The angle shown remains constant. The train is on a level surface. 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 in quantitative terms.
