I had a great physics class yesterday. We had an hour and twenty minutes, so my teacher gave us a spring, an few masses, and an object of unknown mass and told us to figure out the mass of the unknown object.
He gave us no further instruction, and let us run around the room setting up systems for the experiment. It was actually really fun. I also had a great lab group, so that helped.
The lesson was to teach us problem solving at the most basic level: How do you design and execute an experiment?
I am a bit concerned about the grading. The grade will be out of 10 points. 5 points for accuracy and 5 points for the write-up. If our guess for the unknown mass is within 2%, we get 5 points. If it is within 5%, we get 4 points. If it is within 10%, we get 3 points. 10% seems most reasonable, but that already gives you a 70%.
Fortunately, I am confident in our results. We did some linear regression and found that we had a 99.9% match, which is pretty much unheard of, so our equation is very acurate.
I dropped the Spanish class. Now I get to take Latin American history in Spanish. I'm actually pretty excited about it. This will be the first time in two years that I am excited about every single one of my classes. I am super happy. Enjoying class really helps with learning.
Also, Spanish is of course taught in Spanish. I haven't heard English in a Spanish class since sixth grade. This is my fifth year of Spanish, which is beyond the requirement for most schools. Most schools only require three years.
I also took the Spanish 4 AP Exam last year, and I scored well enough that most universities will recognize my score as credit for their language requirement as well.
5 comments:
How Long Has The New Banner Been Up?
Very nice, Jason! Great artwork. It seems you are bolder and bolder.
Have you decided about rents first?
The physics teacher sounds very good.
How many days left until graduation?
s in c
.
.
jason
Got to love physics and thikning for your selves
take care and be safe
bob
Let's see if I can do your physics problem. Let x be the distance a spring stretches when it suspends a mass M. These are related by M*g = k*x, where g is the gravitational constant and k is the spring constant. It follows that M = (k/g)*x. The plot of M versus x is a straight line with a slope (k/g). From this plot for the known masses, the slope can be determined by a linear regression analysis. Knowing this slope, the unknown mass is obtained by multiplying the calculated value of (k/g) by the displacement when the unknown mass is suspended by the spring. Of course, the spring cannot be stretched outside its linear range. Am I right?
--dB
Anonymous is correct, but we didnt do it exactly as you said. I suppose in theory, we did the same thing, we just divided and multiplied different things by other things. Same equation, different process.
We did experiments with the known mass in order to determine k for the spring. Then we found x for the unknown mass and used the known k value and simply plugged it all into the equation and solved for M. Same thing as you said, but no regression analysis.
Another solution that we also did was to graph x versus M and oscillation frequency versus M. We did regression analysis for these data sets, and then plugged in the known x and/or oscillation frequency for the unknown mass and found the corresponding M.
MY classmates all used the last two methods. My group was the only group that actually used the equation for a spring. As I said, the teacher gave us no resources, so my group was the most resourceful in that we opened the textbook to the section on springs in order to check our work.
Lo siento por los muchos comentarios, pero estoy encontrando su blog muy interesante. Posible es que estás de So Cal también o posible es que estás en la universidad y trabajando con su sexualidad- una cosa que me tomó 20 anos a aceptar.
¡Bien trabajo!
Post a Comment