Day 90
NEXT YEAR CUT or significantly reduce THE car crash thing from day 91. Replace with and/or add in rubric and...?
Goals: SWBAT...
1. Define Elastic, Inelastic, and Perfectly Inelastic Collision
2. To solve momentum conservation problems related to Inelastic & Elastic Collisions
Warm-Up 90 (5min): elastic and inelastic (need help? look at the HW notes from day 88 and 89)
1. Rank the three collision types from highest deformation to lowest deformation
2. What important piece of information is given by the following statement? "when doing problems involving perfectly inelastic collisions, recall that the objects stick together after the collision"
3. Find the final velocity after a perfectly inelastic collision with two objects, both of mass 2kg, one with v=2m/s, the other with v=-6m/s
football players during a tackle
CLASSWORK
1. 088B: Review Perfectly Inelastic Collisions - What are they?
Edpuzzle questions: https://edpuzzle.com/media/58864ac2fc574b4961343efd
2. 090A: Elastic 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 elastic 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
3. #090B: Momentum and Impulse Practice Quiz
https://docs.google.com/document/d/1AOzEUF6tEp04fKQuRMjFcKv34VxRi7ADsK4M1czPnP4/edit?usp=sharing
Learning At Home / HW:
- Complete Classwork 88-90
- 090C: Elastic Collisions. (I will check this friday during our notebook check)
Take notes (https://www.flippingphysics.com/uploads/2/1/1/0/21103672/0184_lecture_notes_-_introductory_elastic_collision_problem_demonstration.pdf) and....
Answer Edpuzzle questions: https://edpuzzle.com/media/5899e7d12907083e46c9dd03
- Real Conservation of Momentum Quiz Friday
ESSENTIAL QUESTION: Momentum - Is It Conserved?
Goals: SWBAT...
1. To solve momentum conservation problems
Warm-Up 90 (5min):
1. The billiard balls each have a mass of 0.25 kg. The cue ball is moving at 4 m/s towards another ball
at rest. The cue ball (mass 1) stops after hitting the other ball (mass 2), which moves away.
a. What is conserved?
b. What is the final velocity of mass 2? Back up your answer by solving the appropriate equation
2. The billiard balls each have a mass of 0.25 kg. The cue ball is moving at 4 m/s towards another ball
at rest. The cue ball (mass 1) stops after hitting the other ball (mass 2), which stays stationary (it doesn't move during, or after, the collision).
a. What is conserved?
b. What is the final velocity of mass 2?
c. Was the system isolated? Why yes, or why not?
CLASSWORK
1. #090A: Conservation of Momentum Practice Problems
Solve problems 5c - 14 in your notebook.
Notes: For 5c, post-collision the cue ball moves backwards at a velocity of -3m/s
For the hockey problems, the players are moving in opposite directions. Think about why that matters.
LINK: https://drive.google.com/file/d/0B-AiPYEb3nFVZVJQekNiUjRGcG8/view
2. Complete any missing or late assignments
Learning at Home/HW
- Complete the CW from today
- Watch a video on elastic collisions, and take notes/answer edpuzzle questions.
Be sure to make the "Type of Collision" table in your notes
- Edpuzzle LINK: https://edpuzzle.com/media/58864a5f75bd5044d59d2273
Solutions to Quiz #1 Version 1
WARM-UP (10 minutes)
Today we will be using a light bulb, wire, and battery to create successful and unsuccessful circuits. To best understand why some setups work, and others don't, draw & label three anatomy diagrams; wire, bulb, battery.
(this is your ticket to today's inquiry activity)
Here are some key vocab terms you should use: (BULB: glass, inert gas, wire or filament, metal bump, metal screw part, metal base, black belt, WIRE: wire, insulation. BATTERY: cathode, anode, electrolyte, separator, positive terminal, negative terminal)
CLASSWORK
090A: Creating a Circuit (part 1)
You can work by yourself, or with one partner.
You'll get a single wire, 1.5V bulb, and 1.5V AA battery.
Your job: discover at least four different ways to complete a circuit
Procedure:
1. Predict a configuration of the materials that you think might light the bulb. (need ideas? LINK)
2. Test your configuration.
3. Using the Observation Form (see board), record a diagram of your prediction and whether or not the bulb lit.
4. Make and record other quantitative and qualitative observations (AKA, say why it .
5. Repeat steps 1–4 until you have identified at least 4 different ways the bulb will light and 6 different ways the bulb will not light.
090B: Creating a More Advanced Circuit (part 2)
RULE: ONLY USE ONE BATTERY
You will now combine materials with another person/group. That means you can use two bulbs, and up to two wires, but ONLY ONE BATTERY (more could overload the bulb, just like the LED yesterday, and I don't have any extra bulbs).
just like in #090A, create three configurations that light BOTH BULBS. Diagram them, as well as three configurations which don't work, and make observations.
HOMEWORK:
What is current? How can we calculate the current flow through a wire? All will be answered.....in the 1st Flipping Physics video ever :-)
----->LINK
Questions:
1. Define "current"
2. Which of the following flows in wires? Proton, Electron, Neutron?
3. What is the direction "conventional current" would flow?
4. Copy the image of the Bohr Model of the atom. Where are the electron shells?
5. What's actually flowing, positive or negative charges?
6. So, again, which way does current flow?
7. Energy gets transmitted from a power plant to our homes/school via AC, but most of our devices use a transformer to convert to DC. Why?
8. Solve the current problem ("A") along with Mr. P
9. In the equation, Q=ne what do each of the variables (letters) stand for?
10. Solve for the number of electrons flowing through the wire
11. is that a lot of electrons?