DAY 40
Goals:
- pass the test
- 4 on the notebook check
- do the HW
Warm-Up
- none
Classwork
040A: Exam
- Kiosk App for Schoology
- calculator
- scratch paper
040B: Notebook Check
- days 36-39
- I will call you up to my desk to check your notebook
040C: Reflect on Today
- how was the test? Rank your success from 1-10.
- Why do you think you were/were not successful? Will you change anything (for example, do all the homework, and write it
down) for next week?
- Same questions for the notebook check.
Learning at Home (HW)
1. Free Body Diagrams - What are they?
- Video Edpuzzle LINK
- Sample Notes LINK
2. Lab #3: Ball in a Cup
- Due Saturday 11:59
- last day to test is today
More of next week's homework will be posted here later today. If you'd like to do it ahead of time (over the weekend), feel free.
#Goals: SWBAT...
1. define inertia
2. explain how object's move when forces are unbalanced and balanced
3. Answer inertia related questions
Warm-Up (5min)
Copy and fill in the correct answers for the following:
1. Blood rushes from your ______ to your ____ while quickly stopping when riding on a descending elevator.
2. To dislodge ketchup from the bottom of a ketchup bottle, it is often turned ______ down and thrusted downward at high speeds and then abruptly ______.
3. Headrests are placed in cars to prevent whiplash injuries during _________ collisions.
4. While riding a skateboard (or wagon or bicycle), you fly _______ off the board when hitting a curb or rock or other object that abruptly halts the motion of the skateboard.
CLASSWORK
PSA...
1. #040A: HW Review:
Make two lists, one with examples of contact forces, and one with non-contact (field) forces
What is unique about field forces?
Inertia: The tendency of an object to resist a change in state of motion. A “change in state of motion” means a change in an object’s velocity. a = Δv/Δt , therefore inertia can also be defined as: The tendency of an object to resist acceleration.
2. #040B: Water Demo of Inertia
What is in the plates? Do the plates have tall sides?
We'll have a race, from the sink, to the fire extinguisher, to the projector screen, and back to the sink. If you spill twice, you lose. If you aren't first, you lose.
GO WIN.
Q1: Why is it hard to keep the water in the plate?
Q2: What physics concept does this illustrate?
3. #040C: Practice Questions
LINK Answer 1, 3, 4, 5, 6 (complete outside of class if necessary - I'm here at lunch/nutrition for help)
At Home Learning (HW)
1. Complete the practice problems from #040C (if you didn't finish in class)
2. #040D: read the following: http://www.physicsclassroom.com/class/newtlaws/Lesson-1/Inertia-and-Mass While you're reading, think about how mass and balanced/unbalanced forces affect an object's motion, and answer the following:
a. Who was the first well known scientist to develop the concept of inertia?
b. Looking at the images of inclined planes, how do skateboarders and snowboarders use the concept of inertia to their advantage?
c. The Olympics happened last winter, and there was an event which used these curved "inertial planes" to allow riders to do spectacular aerial tricks. What's the event?
3. #040E:
Inertia & Newton's 1st Law
Take Notes: LINK 1
Watch the video, and answer the EdPuzzle Questions: LINK 2
4. Test revisions are due Monday. See day 39 for instructions...
Save for Monday:
3. #040C: Defining Newton's First Law
Complete the following, and think about the water in the plate:
An object at rest stays at ____ and an object in motion stays in _____ with the same speed and in the same direction unless acted upon by an _________ force.
Copy the image from the board. It's a visual showing the same concepts, and we will fill it in together after I do a demo.
#Goals: SWBAT...
1. Write & understand the equations for Total Mechanical Energy
2. Understand the relationship between work and power
3. Solve basic work & power problems
I'm not checking Day 39 HW today. If you'd have a deep, burning desire to turn it in, I'll give extra credit for it tomorrow.
Warm-Up (4min): The Flow of Mechanical Energy
Read, then complete.
Mechanical energy is the energy that is possessed by an object due to its motion or due to its position. Mechanical energy can be either kinetic energy (energy of motion) or potential energy(stored energy of position).
An object that possesses mechanical energy is able to do work
A classic example involves the massive wrecking ball of a demolition machine. The wrecking ball is a massive object that is swung backwards to a high position and allowed to swing forward into building structure or other object in order to demolish it. Upon hitting the structure, the wrecking ball applies a force to it in order to cause the wall of the structure to be displaced. The diagram below depicts the process by which the mechanical energy of a wrecking ball can be used to do work.
Give three more examples of scenarios in which an object uses mechanical energy to do work
CLASSWORK
1. #040A: Total Mechanical Energy Notes
The Total Mechanical Energy
As already mentioned, the mechanical energy of an object can be the result of its motion (i.e., kinetic energy) and/or the result of its stored energy of position (i.e., potential energy). The total amount of mechanical energy is merely the sum of the potential energy and the kinetic energy. This sum is simply referred to as the total mechanical energy (abbreviated TME).
TME = PE + KE
As discussed earlier, there are two forms of potential energy discussed in our course - gravitational potential energy and elastic potential energy. Given this fact, the above equation can be rewritten:
TME = PEgrav + PEspring + KE
The diagram below depicts the motion of Lee Ben Fardest (esteemed American ski jumper) as he glides down the hill and makes one of his record-setting jumps.
Look at the starting and ending energies. Is energy conserved in this example?
The total mechanical energy of Lee Ben Fardest is the sum of the potential and kinetic energies. The two forms of energy sum up to 50 000 Joules. Notice also that the total mechanical energy of Lee Ben Fardest is a constant value throughout his motion. There are conditions under which the total mechanical energy will be a constant value and conditions under which it will be a changing value. This is the subject of Lesson 2 - the work-energy relationship. For now, merely remember that total mechanical energy is the energy possessed by an object due to either its motion or its stored energy of position. The total amount of mechanical energy is merely the sum of these two forms of energy. And finally, an object with mechanical energy is able to do work on another object.
With that, we're going to tuck this equation for TME away for a while, and pull it out to use again later this week
2. #040B: How Does Work...Work?
Let's learn about the relationship between Work & Power: https://ed.ted.com/on/5bau54uF#review
Read questions 1-9
Watch the video and answer the questions/solve the problems
Discuss :-)
At Home Learning (HW)
1. Complete all 9 questions/problems from #040B
If you got stuck, ask a classmate, or contact me via the Remind App
2. #040C: Wednesday we will continue with Power: Watch/take notes/complete edPuzzle on the following:
I didn't check Day 39 HW today. If you'd have a deep, burning desire to turn it in, I'll give extra credit for it tomorrow.