Journal 9/25

Andrew:

Andrew has draw the normal for the first reflected/incident ray pair correctly. The normal is at a 90 degree angle from the surface. However, from the reflected ray from mirror A to the the reflected ray on Mirror B, the normal is incorrect because it is not on a 90 degree angle from the surface of the mirror. What Andrew needs to understand is that the normal is not the middle of the angle, but that it is perpendicular to the surface of the mirror.

Brad:

Brad's normal for mirror A and mirror B are correct because they are both perpendicular to the surface on the mirror. However, Brad's angle off of mirror B is incorrect because the angle of the incident ray to the normal ray is not congruent to the angle of the ray between the normal and reflected ray. Brad needs to understand the rule that the angle of the incident and normal is equal to the angle of the reflected and normal.

Christine:

What Christine has draw is correct except that her normal for the angle on mirror B is not perpendicular to the surface of the mirror. She needs to understand (like Andrew) that the normal is not the middle of the angle, but perpendicular to the mirror's surface.

I believe that Brad did the best work overall because although his angles were off, he still remembered where the normal was supposed to be placed. His angles were only slightly off, so overall he did the best work.

Journal Entry 9/18

In class, I figured something out without a book or a straight, boring, conceptual lecture. Instead, I learned by doing, by disscussing and by thinking. I learned a lot in class today. I learned that when a light bulb emits light, its light rays do not emit in straight, direct lines with each spot on the light bulb emitting one straight ray, in fact, these bulbs produce rays that shoot out in many different directions that have rays within them that shoot out in all different directions productiong a "glow" affect as opposed to many concentrated dots. I believe that this is true because of two reasons. One, when we view light bulbs we do not veiw many overlapping concentrated dots like one would see with a laser. Instead we veiw light bulbs as an overall glow, that produces a consistent light. The second reason that I believe that what I learned was right is because in the experiment, when we poked a hole into the tinfoil, there was not a concentrated light "dot" on the celing on the otherside of the hole. Instead there was a vast glow of the light that covered much more area that even the whole.