ESSENTIAL QUESTION: Momentum - Is It Conserved?
Video Lecture for today is here: https://youtu.be/2tfaf9HdMrk
Goals: SWBAT...
1. Define Elastic, Inelastic, and Perfectly Inelastic Collisions
2. To solve momentum conservation problems related to Inelastic Collisions
Warm-Up 88 (5min): elastic and inelastic (need help? look at the HW notes from day 87)
1. What does 'deformation' mean?
action or process of changing in shape or distorting
2. Which kind of collision involves two objects bouncing off each other?
depending on the amount of deformation, inelastic (some deformation) or elastic (no deformation)
3. Which kind of collision involves two objects sticking to each other?
perfectly inelastic
4. In an elastic collision, what is conserved?
momentum, KE, mass
5. In an inelastic collision, what is conserved?
momentum, mass
6. Give an example of each of the following collision types:
a. elastic Billiard balls, air hockey pucks
b. inelastic any bouncing collision (bouncy ball, baseball/bat, orange/table
c. perfectly inelastic football players during a tackle
ANSWERS TO THE WARM-UP ARE IN WHITE TEXT. JUST HIGHLIGHT ALL THE TEXT ABOVE AND YOU'LL SEE THEM
CLASSWORK
1. 088A: Inelastic Collisions Activity
Purpose: To gather evidence that can be used to support a claim that total system momentum is or is not conserved in an inelastic collision.
Background: The objects involved in a collision are often considered as a system. Provided that the system of two objects is not experiencing a net external impulse , there would be no change in momentum of the system. If one object within the system loses momentum, it is gained by the other object within the system. The combined momentum of both objects would be conserved.
Inelastic Collisions Interactive: https://www.physicsclassroom.com/Physics-Interactives/Momentum-and-Collisions/Collision-Carts/Collision-Carts-Interactive
Example for how to fill in the Momentum Table: https://youtu.be/2tfaf9HdMrk
2. 088B: Perfectly Inelastic Collisions - What are they?
Take notes (https://www.flippingphysics.com/uploads/2/1/1/0/21103672/0183_lecture_notes_-_introductory_perfectly_inelastic_collision_problem_demonstration.pdf) and....
Answer Edpuzzle questions: https://edpuzzle.com/media/58864ac2fc574b4961343efd
Learning At Home / HW:
1. Complete Classwork 88A
2. 088B: Perfectly Inelastic Collisions
Take notes (https://www.flippingphysics.com/uploads/2/1/1/0/21103672/0183_lecture_notes_-_introductory_perfectly_inelastic_collision_problem_demonstration.pdf) and....
Answer Edpuzzle questions: https://edpuzzle.com/media/58864ac2fc574b4961343efd
3. Notebook check next Friday. All your warm-ups, classwork, and homework should be labeled and organized in your notebook.
ESSENTIAL QUESTION: Momentum - Is It Conserved?
Goals: SWBAT...
1. To solve momentum and momentum conservation problems
2. To determine if momentum is conserved during explosions
Warm-Up 87 (5min):
Consider a system with two carts. Cart 1 is moving to the right with a momentum of 120kgm/s & cart 2 is stationary. Both carts have a mass of 150kg each. The collide, stick together, and roll to the right.
1. What is the total final momentum after the collision?
2. Find the final velocity (post collision) of the carts.
Need help? Stuck? When you've gone as far as you can, here'a helpful video: http://www.youtube.com/watch?v=FitfUuwcfcI
CLASSWORK
1. #088A: Momentum Practice Problems
Solve the following problems in your notebook.
LINK: https://drive.google.com/file/d/0B-AiPYEb3nFVMGRmVkt2ejAzbDQ/view
Get your work signed by Mr. Garcia at the end of the period
Some notes on yesterday's assignment...
2. #087A: Exploding Carts Interactive
- Your job was to choose a variety of mass combinations for the exploding carts, then look for patterns, and come up with relationships and an equation. If you need help with that, here's a video: http://www.youtube.com/watch?v=xVTGkwrvdyE
- Similar to the Fish Catch, today you'll be collecting data, looking for patterns, finding direct or inverse proportionality, and coming up with a rule (equation) to describe the carts behavior. To do that, you will analyze explosions which propel two stationary carts in opposite directions.
- Copy all data tables into your notes
- Collect data
- Answer all questions (1-9)
- Questions/Handout LINK: https://www.physicsclassroom.com/getattachment/Physics-Interactives/Momentum-and-Collisions/Exploding-Carts/Exploding-Carts-Activity/ExplodingCarts.pdf?ext=.pdf
- Interactive LINK: https://www.physicsclassroom.com/Physics-Interactives/Momentum-and-Collisions/Exploding-Carts/Exploding-Carts-Interactive
Learning at Home/HW
- Complete the CW from today
GOALS:
SWBAT understand the basic properties of electric charge.
compare electric force with gravitational force.
explain why a charged object in an electric field is considered to have electrical potential energy.
Express the units for electric potential.
Distinguish between potential and potential difference.
Solve problems using potential in uniform electric fields.
WARM-UP
Where might you find a circuit? List at least 5 places.
What is the purpose of a circuit?
CLASSWORK
1. Circuits Pre-Assessment
Lets see what you already know about current and circuits. Later, we'll do this assessment again, and see how much you've learned
You'll be looking at a number of wiring setups involving a simple circuit (light bulb).
Ignore the portions of the instructions which tell you to 'tap' on the image. It won't work.
For the first 12 questions, you'll need to decide which arrangements of wire, bulb, and battery result in a lit bulb. Occasionally, two scenarios will work. In that case, choose both.
To document your answer, write the letter of the answer. For questions 1-12, call the left setup "A", middle "B", and right "C".
Complete 1-30
Assessment LINK
2. HW Review
3. Electric Potential Difference
- take notes, answer practice questions
- Slideshow: LINK
ANNOUNCEMENTS
1. Friction Rods Activity is due today
2. Complete the Handout on Electric Fields and Electric Field Lines (2 sides) (extra copies are on the seat next to my computer, or links to the handouts are on Day 86). Due Monday. Note: There will be a video posted here on Friday (LINK) covering how to complete the table in problem number 9.
3. Practice problems from Friday (today in class) are due Monday.
4. Extra Credit Opportunities: Due by Wednesday
A. 20 classwork points: Complete all four electric field charts correctly. Incorrect = zero points LINK
B. 10 homework points: Complete the Polarization activity (print out the handout, or recreate the drawing on a piece of paper) here: LINK
HOMEWORK
Video: LINK
Questions:
1. What is the equation for electric potential difference?
2. What are the dimensions of electric potential difference?
3. What is the symbol for electric potential difference?
4. Write the equation for electric potential difference in terms of electric field strength and displacement.
5. Is ΔV a vector or scalar?