WARM-UP (10/25/16)
A spaceship far from any star or planet experiences uniform acceleration from 65.0 m/s to 162.0 m/s in 10.0 s.
1. Why is it important that the spaceship is far from any star or planet?
2. How far does it move?
HINT: Use G.U.E.S.S. method to solve this problem
CLASSWORK
1. What makes a good procedure, good?
Handout (Here is the LINK, in case you're absent)
I have colored pencils by my desk in case you'd like to do some advanced highlighting :-)
We'll do a Think-Pair-Share with this, so make sure it's good. You'll have an audience ;-)
2. Free-Fall Lab
You'll need to log in to a school Google account to submit this on Wednesday (/ . Try out your account now...
A. First, review the lab instructions here: LINK
You'll need to make a copy of the lab report. Once you've saved a copy, share it with your group-mates.
B. Second, write down any questions you have on the board by the struggle zone
C. Third, choose roles for this lab LINK
D. Begin!! Fill in data tables, answer questions, work on the procedure, analysis, etc.
3. Lab Report
SOME TIPS ON WRITING LAB REPORTS: http://www.chem.ucla.edu/~gchemlab/labnotebook_web.htm
Here's what needs to be included in your lab report:
Introduction
Materials: List all the materials used in your experiment.
Procedure: List all steps that your group followed in this experiment. Include diagrams of your experimental setup. Your procedure should be detailed enough that another group could follow your steps and get the same conclusions.
Data: Data should be listed in data tables. There should be one data table for each trial.
Analysis: Answer the analysis questions.
Conclusion: Include the following components:
What you did: Reiterate your procedures briefly (including any changes you made).
What you found: Restate any results that you may have calculated (with errors if applicable). You don't need to include the raw data, but if you calculated an average over several trials, state the average (not each trial). Usually you want to report the results as x +/- y (like 2.345 +/- 0.003), where y is the absolute error in x. In this case, you're comparing measured acceleration with actual acceleration
What you think: What do your results mean? Are they good? Bad? Why or why not? Basically, comment on the results. If your experimental error (RAD, RSD) is small or large compared to the inherent error (the error in the standards and equipment used), comment on what this means, too.
Errors: Speculate on possible sources of error. For the error portion:
What sources of error did you identify during your experiment?
How many sources of error were sources that your team had control over?
For one of the sources of error you identified in #2, suggest a possible way to change the experiment to minimize that source of error.
HOMEWORK
Quiz next class on 3.3 (free-fall) problems
Copy the problem and answer the questions: https://edpuzzle.com/media/5787f4d0a163208e0e7433f6
GOALS:
SWBAT:
1. describe difference between mass & weight
2. Draw a basic FBD
3. Solve a variety of acceleration-related problems
Acceleration Lab Due
WARM-UP:
1. What is a force?
2. What is the difference between mass and weight?
CLASSWORK:
Reading Quiz:
- Take out a 1/2 sheet of paper (5 min quiz)
Mass vs. Weight Notes
- http://www.flippingphysics.com/weight-not-mass.html
Base Dimensions: Mass Weight
SI (Metric) System Kilogram
English (Standard) System Slug Pound
Mass is a measure of the amount of material in an object, being directly related to the number and type of atoms present in the object. It's the amount of "stuff" in an object. Mass does not change with a body's position, movement or alteration of its shape, unless material is added or removed.
An object with a mass of 1 kg on earth would have the same mass of 1 kg on the moon
Weight is the gravitational force acting on a body mass. The generic expression of Newton's Second Law (F=ma) can be transformed to express weight as a force by replacing the acceleration - a - with the acceleration of gravity - g - as
W = m g (2)
where
W = weight or gravitational force - F (N, lbf)
m = mass (kg, slugs)
g = acceleration of gravity on earth (9.81 m/s2, 32.17405 ft/s2)
Intro to Free-Body Diagrams
https://www.youtube.com/watch?v=29YPIvj1zjc
HW Review:
Pg 89: 1-3
Practice for Acceleration Written Test
- We will have the acceleration written test this Friday.
- The test will include 5-7 problems, as well as 2-3 reading related questions. I will also ask you to define the rules of free-fall and terms like "acceleration".
- Today is the last chance to solve practice problems with Mr Alexander.
- Individually, practice by solving the following problems:
Chapter 3, Page 81, # 80, 81, 82, 85, 90, 92, 100, 102, 110
- Prep for Exam:
Equation sheet is allowed (equations only)
1/2 sheet of notes allowed
Review
Each group will be responsible for posting and explaining one of the solutions on the board. Problem assignments are as follows:
82: Black Shadow (Ramon) 82: SQUAD (Ricky)
85: Zero Gravity (Monique) 85: Triple Dream Squad Krew (of Zircon) (Ariella)
90: Synergy Squad (John) 90: West Coast Physics (Parker)
92: Hustlin Honey's (Koraima) 92: Nasals (Patty)
100: OG Pretty Thugs (Jaden) 100: The Asmaras (Asmara)
110: Velocity Raptors (Esai) 110: Straight Outta Physics (Xiomara)
Answers:
80: 8.0m/s2
81: 33m/s
82: a. 6.0m/s2 b: 0.0m/s2 c. -2.0m/s2 d. -4.0m/s2
85: Car B is greatest at 6.4m/s2
90: a: 140m b: 550m (about 4x farther at double the speed)
92: 920m
100: 7.3m/s
102: a: 6.2m b: 11m/s
110: a: 247m/s2 or 25 times greater than g (gravity)
b: 207m/s2 or 21 times greater than g (gravity)
HOMEWORK:
TUESDAY:
Do pg 89 4-5 & Read pg 90-93
Define "Net Force" & "Newton's Second Law"
EXAM on Tuesday, 10/27 (bring 1/2 sheet of notes + equation sheet)
THURSDAY:
Do pg 93 #8; pg 95 #9-10
Define "Inertia" & "Equilibrium"