Well Here Goes...

Sooo..... This is my first post of my very first blog so let's see how it goes.

 

Hello blogging world, I'm Heather and I'll be starting this blog to write down and keep track of my thoughts and labs for my freshman physics class this year. Anyway, down to business...

 

This last week we had a "laborama" (not as fun as it may seem) in class. After we finished, our class had a board discussion where we write all of the lab info (question, prediction graph, set-up, data, real graph, and conclusion)  on a big whiteboard and compare our results.

 

#1.Circle Lab

Our first lab compared the relationship between diameter and circumference of circles (a.k.a. random lids) . During this lab we realized a few key things:

 

1)     The 5% Rule –

Data is sometimes off and can be effected by systematical error. This can lead to misleading formulas based on inaccurate data, including y-intercepts that should not exist. If you take the y-intercept and divide it by the highest "y" data point then multiply it by 100, the product must be under 5 for the data to be acceptable.

 

2)     Added (0,0) –

While doing Circle Lab #1, one thing became a problem when we started to graph our data. It was self evident when a circle has no diameter, it won't have a circumference because there is no circle. So our class discussed adding (0,0) as a point because logically that makes sense. Then, the trendline produced might more accurately describe the data.

 

 

 

3)     Making An Accurate Graph -

First one must determine the type of function (linear, quadratic, exponential, powers, or polynomial) their data fits. Then one has to figure out the units for the graph. The "x" variable, or independent variable, is easier because you physically use it to take the data. The "y" variable can be a little harder. To figure this out, you must combine the units used in the equation by division, multiplication, or cross-cancelation.

 

Along with these key realizations, our class discovered the true relation between the diameter and circumference of a circle. Since we know the formula of circumference is C=2• π• r and d= 2• r, we were able to make the connection that C= π•d. For every 1 cm of diameter, circumference increases by about 3.14, or π, cm.

Until next time.....