Kinetic friction

Laboratory five focused on the force of kinetic friction. 

Preset was laid out between 8:00 and 8:16

The large class and dearth of slot weights, coupled with an inability to easily order replacement weights, has each group working with four unique weights. With permutations and combinatorics, this provides ten data points. Data sheets were preprinted this term. No mass balances were brought to the laboratory: the sled is treated as zero when unloaded. This generates a y-intercept for all of the groups and thus a y=mx+b regression equation for the first time this term. This also makes the weight calculations much easier. 


The morning notes were brief and light.


After the 8:00 section the coefficients of friction were posted to the board. 


Four weight rigs were set up on the outer tables using primarily green spring scales (500 gram-force max). 


The center table was set up with two grit rigs and blue spring scales (250 gram-force max).


Weight rigs


Weight rig detail

Desmos



Veronica holds the sandpaper, Grace Marie records data

Bracey records data while McCordy handles the experimental rig.

Bracey holding the sandpaper while McCordy makes a reading.

Damien reads the spring scale while Melansha records data. 

Jerson records data while Trusty takes readings


Roselihn measures the force of friction for a grit set. There are three 100 gram masses on the sled to add downforce to the sled. Iryann selects the next grit size.

Iryann, Roselihn, and Maicalany ener their data into Desmos.

Jerson enters data into Desmos, Ashton had just arrived. Damien and Meilansha working on entering the regression equation.

Aquillera joined Veronica and Grace Marie after data gathering had occurred.


Grace Marie takes notes by photographing the board.

Midday heat 



Moki, Kayla, and Franchesca working with weights


Haily Eva and Marikai readying to make a measurement

Franchesca making a measurement

Trevor ready to record data, Trishelle setting up the sled, Finley selecting the grit

Trishelle setting up for a test run with 538 micrometer grit size sandpaper

Desmos


Board notes at the end of the 11:00 section

More coefficients of friction from the 11:00 section.

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