![Page 1: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/1.jpg)
Can we create measuring device using our observed properties of light?
What would we need to know to determine if our device was accurate?
![Page 2: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/2.jpg)
How do we know our spring scales are accurate?
1 kg
![Page 3: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/3.jpg)
How do we know spring scales are accurate?
1 kg 4 kg2 kg
0 1 2 3 4 5 60.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
stre
tch
(cm
)
mass (kg)
offset or “blank”
![Page 4: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/4.jpg)
How do we know spring scales are accurate?
1 kg 4 kg2 kg
0 1 2 3 4 5 60.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
stre
tch
(cm
)
mass (kg)
1 kg
![Page 5: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/5.jpg)
SI Units and time
![Page 6: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/6.jpg)
How do we know spring scales are accurate?
1 kg 4 kg2 kg
0 1 2 3 4 5 60.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
stre
tch
(cm
)
mass (kg)
2 kg
![Page 7: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/7.jpg)
How do we know spring scales are accurate?
1 kg 4 kg2 kg
0 1 2 3 4 5 60.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
stre
tch
(cm
)
mass (kg)
![Page 8: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/8.jpg)
How do we know spring scales are accurate?
1 kg 4 kg2 kg
0 1 2 3 4 5 60.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
stre
tch
(cm
)
mass (kg)
![Page 9: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/9.jpg)
How do we know spring scales are accurate?
1 kg 4 kg2 kg
0 1 2 3 4 5 60.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
stre
tch
(cm
)
mass (kg)
![Page 10: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/10.jpg)
How do we know spring scales are accurate?
1 kg 4 kg2 kg
0 1 2 3 4 5 60.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
stre
tch
(cm
)
mass (kg)
![Page 11: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/11.jpg)
How do we know spring scales are accurate?
0 1 2 3 4 5 60.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
stre
tch
(cm
)
mass (kg)
Calibration curve
What mass causes a stretch of 5.5 cm?
=4.34 kgFinal calibration dataStretch = mass (1.13) + 0.60Mass = (stretch – 0.60) / 1.135.5 cm
![Page 12: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/12.jpg)
What would we need to know to make an accurate calibration curve for our
device?
Tank of milk and water
light sensor
![Page 13: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/13.jpg)
Let’s look at milk fat globules in water
+using serial dilutions
![Page 14: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/14.jpg)
0.2 mm diameter FOV
Homogenized milk contains many small globules of fat
Each mL of 2% milk contains about 10 million globules
…this “population density” is about 1010 globules/L
Visible light is scattered nicely by these globules, about 5 m across on average
Why milk?
About 10 m diameter glob is a big one
ten billion
Which is the size of many exxtremophile microbes we’ll be looking for .
![Page 15: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/15.jpg)
The intensity of light that is transmitted decreases when the
milk fat density. . .
(millions of globules per liter)
(photoresistorvoltage) What will the
graph look like?
…what would our measurements be?
![Page 16: Can we create measuring device using our observed properties of light?](https://reader035.vdocument.in/reader035/viewer/2022070420/56815e6f550346895dccf06f/html5/thumbnails/16.jpg)
Will the calibration curve be similar for a smaller device utilizing the
same properties of light?• Insert picture & explanation of handheld
spec here