get your normal off my refracted lens

we have been discussing incident rays and rays of reflection and refraction. when a ray passes from one medium to another (i.e., from air to water), the ray is refracted, or changes its path based on its change in speed. if the ray goes from fast to slow (like from air to water), the ray bends TOWARD the normal, or the line perpendicular to the surface. if the ray goes from slow to fast, the refracted ray bends AWAY FROM the normal.

so i'm going through examples in class and as i'm drawing out the refracted rays, i find myself saying "fast to slow, towards the no'." ok.. that's good. not a bad way to remember it. then comes the other situation. "slow to fast....... um... get off my normal." so that's what it's become. "slow to fast, get off my normal." for those kids that didn't seem to get it, i reminded them that i can't say "ass" 50 times a class so we have to use "normal."

i can't tell you how hard i laughed today when i handed out worksheets and kept hearing students muttering to themselves "slow to fast, get off my normal" or any of the other variations that have developed: "slow to fast, stay away from my normal," "slow to fast, move away from my normal," "slow to fast, don't smoke my grass." also, today at lunch michael told me that tenelia tried touching his normal. this mantra is taking on a life of its own and it's amazing. i can only hope these kids are muttering it years from now in some geometry class.

bees do what?

our latest unit has been on waves and their properties. i was giving a lecture on the behavior of waves (reflection, refraction, diffraction and the like) and was half-way through a sentence on how the angle of incidence in reflection is equal to the angle of reflection when all of a sudden mr. kennedy blurts out "DO BEES LAY EGGS?" hmm... interesting question. "CUS I MEAN.. DO BABY BEES COME OUT, OR ARE THEY EGGS?" it was kind of like the thought came into his head and very quickly that thought traveled to his lips and became sound waves that made it to my little ear drums. i asked him if his question had anything to do with what we were talking about, he said no.. and then i told him no, i don't think bees lay eggs. i think larvae is somehow involved. and back to the angle of reflection.

Hertz, donut

1- the pictures are of the 2009 baltimore kinetic sculpture race that about 15 of my students and i were a part of this year. i plan on being in this race every year for the rest of my life. 15 miles. mud pits, floating in the dirty harbor, boas and fun socks and more costumes than you could shake a goggle at. SO MUCH FUN.

2-our new unit is on waves and sound. today we were talking about what frequency is, a period is, all that fun stuff. i asked what frequency was measured in, to which the students responded "Hertz." i then asked if they had ever had a Hertz donut. they said no. poor unsuspecting bastards. i walked up to a select member of each class (jabrea, nigel, soren) and asked if they wanted a Hertz donut. they each said yes, and i slugged them in the arm and said "hurts, don't it?" yeah... they had never heard that before. and now i'm assuming there are 8th graders all over the city with huge Hertz donut bruises on their arms.

we also discussed what a "period" is (the amount of time it takes one wavelength to pass a given point). when i asked for students to define it, i made sure to tell them first that no, it was not when a girl becomes a woman. they gave me the right definition. i then asked them what it was measured in.... "is it teaspoons? no... periods are measured in seconds." apparently i'm that gross science teacher. SO many groans and disgusted faces. right on.