Wright State University Lake Campus/2019-9/Oil drop kinematics
- Youtube: Oil drop diagrams Note provocative comment about using videos instead of teachers.
- Pilot pages: Phy1010 . HTW
- Content moved here from:
- Wright State University Lake Campus/2019-9/Phy 1050/Notes How Things Work (HTW)
- Wright State University Lake Campus/2019-9/Phy 1110/Notes College Physics (CP1)
Initial effort by HTW
[edit | edit source]08-28W
[edit | edit source]- Mozart D-minor piano 126-132 beats per minute. We got 150 beats/min. Is this a big deal? 150/129=1.16
- https://www.youtube.com/watch?v=7QgOBbKl0eY
Buzzwords (vocabulary):
inclined plane ...
rise and run ...
uniform sphere ...
Galileo's rule of 1, 3, 5, 7 ...
uncertainty/error
08-29R
[edit | edit source]Took data on solid sphere rolling down incline
At beat t=-1 ball was relased. Distances from release point shown shown in centmeters for three trials (a,b,c). We conducted four trials. The rise was 3.1±.1 cm, and the hypotenus was 138±1 cm. I am not sure where the ball was released: 0 cm or 0.5cm?
The accelerations are shown on the right, it seems to be the median suggests that it's 14 + or - 4 cm/s2.
t | a | b | c | * | Dt (sec) | a | b | c | h | ell | frac 7/5 | a(med) | g(meas) |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0 | 2 | 2 | 2 | * | 1.6 | ||||||||
1 | 32 | 30 | 33 | * | 1.6 | 10 | 13.75 | 23.125 | 3 | 138 | 1.4 | 13.75 | 885.5 |
2 | 78 | 80 | 101 | * | 1.6 | 13.125 | 20 | 2.5 | 3 | 138 | 1.4 | 13.125 | 845.25 |
3 | 145 | 162 | 173 | * | 1.6 | cm/s/s | cm/s/s | cm/s/s | a(ave) is: | 13.75 | |||
08-30F
[edit | edit source]Same Mozart. From this we conclude that the syncopation error will probably be small. In other words, why switch to more boring music if it doesn't get us better results?
bars | sec | bars/sec | beats/min | sec/bar | |
---|---|---|---|---|---|
15 | 26 | 0.576923077 | 138.4615385 | 1.7333 | |
29 | 45 | 0.644444444 | 154.6666667 | 1.5517 | |
3 | 4.97 | 0.60362173 | 144.8692153 | 1.6567 | |
15 | 23 | 0.652173913 | 156.5217391 | 1.5333 | |
15 | 26.3 | 0.570342205 | 136.8821293 | 1.7533 | |
0.609501074 | 146.2802578 | ave | 1.6457 | ||
0.037654083 | 9.036979948 | sddev | 0.101 | ||
6% | 6% | sd/ave | |||
25% | 25% | off by 1 beat | |||
13% | 13% | half beat | |||
6% | 6% | sd/ave | |||
25% | 25% | off by 1 beat | |||
13% | 13% | half beat |
Data by 1110
[edit | edit source]https://tools.wmflabs.org/excel2wiki/
0 | a1 | a2 | a3 | c1 | c1 | c1 | b1 | b2 | b3 |
---|---|---|---|---|---|---|---|---|---|
1 | 40 | 50 | 46 | 25 | 30 | 32 | 4.5 | 4 | 4 |
2 | 90 | 125 | 122 | 85 | 79 | 97 | 62 | 53 | 45 |
3 | 182 | 200 | 200 | 151 | 163 | 179 | 152 | 158 | 131 |
Formulas
[edit | edit source]Accelerated motion
[edit | edit source]where the moment of inertia of a solid sphere is , and,
is the ratio of height to track-length. A good way to evaluate our accuracy is to solve this for g and see how close it is to the accepted result of approximately 980 cm/s2. For the exact value of g at your location, visit https://www.sensorsone.com/local-gravity-calculator/.
In "How-things-word" we did the algebra to get:
Calculating acceleration
[edit | edit source]It can be shown that for three consecutive locations along straight line: