DAY 134
Goals:
1. Pass the quiz with a score of 100%
Warm-Up:
1. Find the efficiency of a machine with Mechanical Advantage of 0.7 and Ideal Mechanical Advantage of 0.8.
2. What would have a greater Mechanical Advantage?
a. Box sliding up a 10 degree inclined plane or the same box on wheels rolling up a 10 degree inclined plane
b. Box sliding on a greased 10 degree inclined plane or the same box sliding on an ungreased 10 degree plane
Classwork:
1. Warm-Up Answers
1. Eff = MA/IMA * 100 = .7/.8 * 100 = .875*100 = 87.5% --> one sig fig --> 90%
2. box with wheels and the greased box would both lose less of the effort force to friction, and therefore have a greater output (resistance) force, which means they'd have a larger MA.
2. 134A: MA/IMA/Efficiency Quiz
quiz is posted to schoology
You can have a scratch paper sheet with the MA, IMA, and Efficiency equations on it. No notes though. 40 min time limit. Review session for the results of this quiz Wednesday 11:00-11:30 on Zoom. Complete your quiz by 10AM Wednesday.
you'll have a time limit to complete the quiz, so only open the quiz when you're ready to take it.
A retake will be available tomorrow.
If you'd like to review prior to (or after) the quiz, here is a nice resource provided by David Pineda (thanks!). The video reviews MA/IMA/Efficiency, talks about how you can use wheels and grease to increase efficiency, and at the 10min mark, reviews how to solve a variety of problems. What the teacher describes as Actual Mechanical Advantage (AMA) we call Mechanical Advantage (MA).
Last day to work on Rube Goldberg in Room 37 is this Friday. If you still aren't done (why?), you can take it home for spring break. Some evidence of learning is better than no evidence. Some points are better than no points.
Wednesday (today) and Thursday (tmw) will be Science Bowl days at lunch. Unless you are QUIETLY retaking a quiz, getting tutoring, or working on your machine, you'll need to find a different room to hang out for those days.
-Mr. A
GOALS: SWBAT
1. memorize the relationship between frequency and period
2. solve problems involving wavelength, period, and frequency
WARM-UP
1. What is the relationship between frequency and period?
2. A wave is introduced into a thin wire held tight at each end. It has an amplitude of 3.8 cm, a frequency of 51.2 Hz and a distance from a crest to the neighboring trough of 12.8 cm. Determine the period of such a wave.
a. which info is irrevelant?
b. solve the problem
CLASSWORK
134A: Frequency & Period Practice Problems
Solve "Check Your Understanding" #2-11
Each problem should take 30-90 seconds
LINK: https://www.physicsclassroom.com/class/waves/Lesson-2/Frequency-and-Period-of-a-Wave
134B: Wave Speed Practice Problems
Solve "Check Your Understanding" #1-9
Each problem should take 30-120 seconds
LINK: https://www.physicsclassroom.com/class/waves/Lesson-2/The-Speed-of-a-Wave
LEARNING AT HOME (HW)/Announcements
1. Complete 132A and B and 134A & B. Quiz coming Friday, so you'll want your wave math skills to be sharp
Need help? Videos are below...
https://www.youtube.com/watch?v=1E5IcxtWktc
https://www.youtube.com/watch?v=3-wSHmXB64o
2. Lab 133A due Thursday
More hands on wave practice in class Thursday
3. Quiz on wave parts/labeling/definitions and wave problem solving Friday