SHM and Waves Practice Test

Today is your work time to study for your test next Wednesday. Below are the practice test, key, and solutions videos.

Simple Harmonic Motion PRACTICE TEST
Answer Key

Solutions videos:
#7
#8
#9
#10

Have a great Rodeo Break.

Sound Intro

Today we went over a bunch of stuff about sound:

Notes: Sound

Your only homework is to read section 14.2 in the textbook and then explain what you read to another person. We'll have some bellwork next week based on the reading, but otherwise I'm just trusting you to read it.

Please note that this information is NOT on the next unit test. Because of Rodeo Break this week and the ACT next week we just needed to start the next unit before the last unit's test, which will be next Wednesday.

Speaking of the test, you also might have picked up a practice SHM motion and Waves test today. You will have a work day tomorrow.

Wave Interference and Reflection

Today we talked about what happens when waves overlap or hit a barrier/change mediums.

Notes
Simulations:
Zona Land Education: Wave Interference I
Zona Land Education: Wave Interference II
Zona Land Education: Wave Interference III
PhET: Wave on a String

Homework: Ch. 13 (p.470) #61, 64, 65

Earthquakes and Electromagnetic Radiation

Today was slightly short because of the pep assembly, so we just talked about earthquakes and electromagnetic (EM) waves. Below is a picture of what ended up on the board:

We also visited these sites or watched these videos:

Types of Seismic Waves (L. Braile, Purdue)
Seismic Waves (YouTube)
Seismic Wave Propagation (Michael S. Thorne, H. Philip Crotwell, Gunnar Jahnke, and Heiner Igel)
Electromagnetic Spectrum
United States Frequency Allocations (NASA)

Homework: p. 469 #43, 45, 46

Mechanical Waves

Today we introduced mechanical waves:



Here is a website with animations of the different kids of mechanical waves:

Acoustics and Vibrations Animations, Daniel A. Russell, Pennsylvania State University

Homework: Ch. 13 (p.469) # #41, 42, 44

Period of a Pendulum

Today we used your lab results to get the equation for the period of a simple pendulum. We also watched a fun pendulum video and mentioned physical pendulums.

Notes: Pendulums

In case you can't access the Powerpoint, here are the links for the videos we watched:


Harvard Natural Sciences Lecture Demonstrations: Pendulum Waves
Memo Akten: SHM #2 Excerpt
Somewhere in here we also talked about speed walking and pendulums, so here is a video of speed walkers.

Homework is Ch. 13 (p. 468) #34, 35, 39

Lab: Period of a Pendulum

Today we basically did the same lab as last week, except for a pendulum instead of a spring on a mass:



For any linear graphs you get, try to figure out what the slope represents. Also, don't displace the pendulum by more than 20 degrees.

If you were gone, there is a very nice pendulum simulation here: PhET Pendulum Lab. There is even a lovely photo gate timer that you can turn on that will measure one period for you. If you prefer a standard stopwatch, one will appear if you turn on "other tools."

No extra homework tonight; just get the lab totally finished.

SHM Practice Problems

Today was a half day, so you worked on practice problems while I checked your labs from earlier in the week. These are due next class:

Ch. 13 Conceptual (p.465) #1, 2 + Problems (p. 467) #19, 21, 24, 25, 28

Bring your lab notebook next class! We're doing ANOTHER LAB!

Circles and SHM

Today we used circles to model simple harmonic motion, which gave us some equations for the position, velocity, and acceleration of an object undergoing SHM. We also talked about angular frequency.

Notes ended up on the board (below) and we used these sites to look at the motion:

UNSW School of Physics PhysClips: SHM Background Material

Teresa Martin Physics Flash Animations

If we had time we also watched this (just because it's cool).

Homework is Chapter 13 (p. 467) #12, 18, 22

Springs and Simple Harmonic Motion

Today we used the results from your lab to get an equation for the period of a mass on a spring. We also took a little bit of notes beyond that:

Notes: Simple Harmonic Motion

Homework is a little half-sheet worksheet I made: 2/8 HW (ignore the wrong date on this PDF scan). There is a ranking task on the back side that I cannot reproduce online, so you'll have to get a hard copy in class.

Lab: Period of a Mass on a Spring

Today you completed a lab to determine what and how quantities affect the period of oscillation for a mass on a spring.

Lab: Finding T for a Mass on a Spring

No extra homework tonight, but this lab is due Wednesday.

We ended up with some hints on the board, so there is a picture of it below.

If you missed the lab or didn't get enough data at home, there is an online simulation here:

PhET Mass-Spring Lab

To use it you need to make sure the "friction" is set to zero, time is set to "real time" and the planet is "earth." Use the spring on the far right and change its k value by moving the "softness spring 3" slider. You will have to find the k for each "softness" level by hanging a known weight on the spring and measuring how far it stretches. Then k = mg/x. Finally, you'll need more masses that the labelled ones provided, so I found the masses of the unlabeled colored masses for you: green = 70g, gold = 160g, red = 300g.

Springs!

Today we used your labs to figure out Hooke's Law. We also talked about ways the model of springs can be used to explain concepts that don't necessarily look like springs.

Dolphin Tails
Chemical Bonds
Robert Hooke

Homework: Chapter 13 (p.466) #1, 4, 5

Also bring your lab notebook Monday/Tuesday.

Spring Intro Lab

Today we derived Hooke's Law with a little intro lab:

Spring Intro Lab

The lab is due tomorrow.

Senior Debates

The Senior Debates were today, so I only had periods 5 and 6 in class. They had work time. You may have picked up your take-home test anytime at lunch or later, but if you didn't make sure to pick one up tomorrow.