James Okamura
Daniel Guzman
Rodrigo
Frebruary 27, 2017
In this lab we were trying to measure masses of known and unknown objects that doesn't depend on gravity with a Inertial Balance.
This apparatus is called an Internal Balance and we put a tape on the end with the sensor near the tape. Then when we add known masses we would record what mass we out on, and using Logger Pro, we are able to record the period of the oscillations . With this given data of known masses and respective periods we are able to calculate the measurement of the Internal Balance tray.
This data table is where I recorded the known masses values with its respective periods when using the Internal Balance and Logger Pro.
Using Logger Pro, we were able to get natural log of the period value and the natural log of the known masses. From there we were able to calculate our upper and lower bounds as well as our middle bound by comparing the linear correlations in which we were able to obtain 350 grams and 310 grams ( max and min respectively) with each a correlation of 0.9998.
When we graph with the tray value with 310 grams and 350 grams we were able to calculate the slopes and Y-intercepts from the Logger Pro program.
Using these two formulas, we are now able to find the range of masses of an unknown object using the Internal Balance. We did this by putting an unknown object, (for our case we used a tape dispenser and a calculator ) on the Internal Balance and swung it so that the motion sensor will record its respective period. Using the recorded periods and the the two formulas above, we are able to find the range of masses for the tape dispenser and calculator.
I believe that when we calculated the range of mass values for calculator, there was some for of human error that took place, such as how we placed the calculator, or if interpreted the data wrong so it is not in the range as shown above. When we did the tape dispenser, we got the range to be really close to the actual measurement from a balance.
I believe in this lab , what we did was how to use an internal balance and logger pro to help us find the associatio between the mass of an object to its period.
Right from the get-go it isn't clear what an inertial balance is or how you are going to use it to measure masses.
ReplyDeleteCheck spelling. Internal and inertial are different things.
Why do you put tape on the end? What is the sensor you are using? What information is that sensor going to give you?
Here's what you write: Using Logger Pro, we were able to get natural log of the period value and the natural log of the known masses. From there we were able to calculate our upper and lower bounds as well as our middle bound by comparing the linear correlations in which we were able to obtain 350 grams and 310 grams ( max and min respectively) with each a correlation of 0.9998.
Again, it isn't clear why your are doing what you are doing in the lab. Consider an approach more like this:
--Power law equation
--ln form
--what will be plotted on the y axis and on the x-axis
--what the slope and y-intercept of that graph will tell you
--how you are going to find the mass of the tray
I can't read what is on your graph. You seem to have only one graph, although you should have at least two, one for each of your Mtray values (upper and lower bounds), since these graphs are data.
Your calculations are clear.
When we set up our original equation all of the masses were cylinders centered in the tray. Our unknown objects had different shapes and perhaps different placement in the tray. We didn't test separately to see if placement or shape made a difference. This isn't a human error so much as an assumption (that mass is the only variable) that maybe turns out not to be true.