DAY 155
Link to today's lecture is here: https://youtu.be/cJt0QJYUuE4
ESSENTIAL QUESTION: How can I prove that light is a wave?
Goals:
1. SWBAT list two facts which prove light is a wave
2. understand the ordering of the frequency, wavelength, and energy for the various regions in the continuous spectrum for electromagnetic waves and visible light waves
WARM-UP:
1. 1 nm is 1 nanometer, which is 1 billionth of a meter, or 1x10-9m, or 0.000000001m
2. The acronym ROYGBIV is used to help order the relative wavelength of colors of light. Red is ~650nm, and Violet is ~420nm.
a. Does the order go from low to high, or high to low?
b. Would it make sense for Green to be 670nm? Why?
CLASSWORK:
1. 154A and B: Slideshow link ----->LINK (20min, then 10min review)
Consider that different frequencies of sound waves make different pitch sounds (high, low, and in-between)
How does the fact that different frequencies make different colors prove that light is a wave?
2. 154C: Polarization Demo (5 min)
Wait, what is polarization in relation to E-M waves?
Polarized E-M waves are E-M waves in which the vibrations occur in a single plane.
How does polarization prove that light is a wave?
Demos:
- waves thru fenceposts
- paper thru fenceposts
- polarized glasses (fenceposts) viewing vertically oriented waves from a LCD screen
- https://www.youtube.com/watch?v=dUA6nyvy-LY
3. 154D: The Electromagnetic and Visible Spectra:
To prepare for tomorrow's class, read: http://www.physicsclassroom.com/Class/light/u12l2a.html and answer the three Check Your Understanding questions
Goals: SWBAT...
1. collect data and apply a formula to calculate diameter of human hair
2. Describe the cause of static electricity
3. solve electrostatic force problems
WARM-UP:
1. How many word parts in the word "electrostatic"?
2. Define each word part
3. One Coulomb is about the amount of charge that passes through a common 100 watt lightbulb in about one second. What might you feel if 1 Coulomb of charge passed through your body?
Refraction Lab 153B is due Friday. The lab is short, and should include your answers to prompts #2-5. Type your answers into the template document on Schoology, upload a photo of your handwritten answers, or show me your handwritten lab results in class today or tomorrow. Can't access the document on Schoology? Here's a copy (LINK) which you can upload independently.
CLASSWORK
(waves)
1. 154B (continued)
If you collected your data yesterday, today is the day to make your measurements, and make at least two hair diameter calculations in class.
Unsure of how to proceed? Here's a 5min video showing how to analyze the data and calculate your hair's diameter: LINK
Again, the lab is due Sunday night via Schoology, and there is a lab document template on Schoology (154B)
(electrostatics)
2. Check your answers to last night's guided reading: LINK
3. 155A: What is Static Electricity: Watch the video here: https://ed.ted.com/lessons/the-science-of-static-electricity-anuradha-bhagwat#watch
While watching, in your notes, answer the 7 "Think" questions listed in the Think section of the website (you can also click here (LINK) for the questions. To answer #2, review the brief paragraph below:
"Dry air preferred. Static electricity is formed much better when the air is dry or the humidity is low. When the air is humid, water molecules can collect on the surface of various materials. This can prevent the buildup of electrical charges. The reason has to do with the shape of the water molecule and its own electrical forces."
4. 155B: How attracted are you? (do any 6 for base level (proficient = 5pts), or all 12 for mastery (and 10pts). Solve these on paper. Show in class at end of class, tomorrow, or Monday for full credit. LINK
HW: 155C: Charging by Friction handout
- type your answers into the Google Doc on Schoology (can't access it on schoology? alternate link is HERE)
- answer questions 1-6 only from the following LINK
- unsure of how to answer these? Here's your assistance in two forms, reading and a slideshow:
- slideshow LINK
- reading Structure of Matter LINK1 and Charging by Friction LINK2
FRI:
friction rod activity
complete charging by friction handout 1-12 to show proficiency
HW:
1. Conduction/Induction GUided Reading
2. 080C: Complete all the first two skill builder levels here (LINK): Make sure to use your full name, and to take a screen shot of your two trophies when you're done
The third level is extra credit :-)
3. Lab due sunday