Your 'flow experiment' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
** Your initial message (if any): **
** Is flow rate increasing, decreasing, etc.? **
The rate of flow will decrease because there is progressively less pressure due to the decreased mass of water in the column.
** Is the velocity of the water surface increasing, decreasing, etc.? **
The velocity will decrease.
** How would the velocity of the water surface, the velocity of the exiting water, the diameter of the cylinder and the diameter of the hole be interrelated? **
I expect to be able to calculate that the velocity of the water surface is greater when the velocity of the exiting water is greater (because these are two ends of the same system) when the diameter of the cylinder is greater (because there is more water, more mass, and more pressure) and when the diameter of the whole is greater because more water can escape per unit time.
** Explain how we know that a change in velocity implies the action of a force: **
F=ma. Acceleration is change in velocity of a mass over time. This force is the earth's gravity acting on the column of water.
** Does the depth seem to be changing at a regular rate, at a faster and faster rate, or at a slower and slower rate **
In sequence, the percent change is 20%, 12%, 11%. It decreases at a decreasing rate.
** What do you think a graph of depth vs. time would look like? **
Negative slope that becomes more positive from left to right.
** Does the horizontal distance (the distance to the right, ignoring the up and down distance) traveled by the stream increase or decrease as time goes on? **
It decreases
** Does this distance change at an increasing, decreasing or steady rate? **
Decreasing rate
** What do you think a graph of this horizontal distance vs. time would look like? **
Negative slope that becomes more positive from left to right.
** The contents of TIMER program as you submitted them: **
event number,clock time,time interval
1 , 66.82813 , 66.82813
2 , 67.65625 , 0.125
3 , 68.90625 , 0.1796875
4 , 70.07031 , 0.828125
5 , 71.16406 , 1.09375
6 , 72.57031 , 1.09375
7 , 73.72656 , 1.15625
8 , 75.39063 , 1.164063
9 , 76.48438 , 1.25
10 , 76.60938 , 1.34375
11 , 77.95313 , 1.40625
12 , 79.5 , 1.429688
13 , 80.92969 , 1.546875
14 , 82.58594 , 1.65625
15 , 84.60156 , 1.664063
16 , 86.45313 , 1.851563
17 , 88.76563 , 1.976563
18 , 90.74219 , 2.015625
19 , 93.05469 , 2.3125
20 , 95.76563 , 2.3125
21 , 99.0625 , 2.710938
22 , 99.24219 , 3.296875
23 , 103.5391 , 4.296875
** The vertical positions of the large marks as you reported them, relative to the center of the outflow hole **
.3
1.2
2.0
2.8
3.5
4.4
5.2
5.9
6.7
7.5
8.2
9.0
9.7
10.5
11.2
12.0
12.7
13.4
14.1
14.8
15.6
16.2
16.9
** Your table for depth (in cm) vs clock time (in seconds) **
0.00000,16.9
0.82812,16.2
2.07812,15.6
3.24218,14.8
4.33593,14.1
5.74218,13.4
6.89843,12.7
8.56250,12.0
9.65625,11.2
9.78125,10.5
11.12500,9.7
12.67187,9.0
14.10156,8.2
15.75781,7.5
17.77343,6.7
19.62500,5.9
21.93750,5.2
23.91406,4.4
26.22656,3.5
28.93750,2.8
32.23437,2.0
32.41406,1.2
36.71097,.3
** Is the depth changing at a regular rate, at a faster and faster rate, or at a slower and slower rate? **
As I predicted, the depth decreases at a decreasing rate.
** Your description of your depth vs. t graph: **
Negative slope that becomes more positive from left to right.
** Your explanation and list of average average velocities: **
The distance between large marks appears to be about .007m against my ruler, so I divided .007 by each time interval to get m/s.
0.056
0.038956
0.0084528
0.0064
0.0064
0.00605405
0.00601342
0.0056
0.00520930
0.004978
0.00489617
0.004525
0.0042264
0.0042065
0.0037805
0.0035415
0.0034728
0.00302702
0.00302702
0.00258213
0.0021232
0.0016291
0.0010821
** The midpoints of your time intervals and how you obtained them: **
I added each adjacent pair of time intervals and divided by 2.
0.0625
0.15234375
0.50390625
0.9609375
1.125
1.1601565
1.2070315
1.296875
1.375
1.417969
1.4882815
1.6015625
1.6601565
1.757813
1.914063
1.996094
2.1640625
2.3125
2.511719
3.0039065
3.796875
5.3828125
** Your table of average velocity of water surface vs. clock time: **
0.0625,0.056
0.15234375,0.038956
0.50390625,0.0084528
0.9609375,0.0064
1.125,0.0064
1.1601565,0.00605405
1.2070315,0.00601342
1.296875,0.0056
1.375,0.00520930
1.417969,0.004978
1.4882815,0.00489617
1.6015625,0.004525
1.6601565,0.0042264
1.757813,0.0042065
1.914063,0.0037805
1.996094,0.0035415
2.1640625,0.0034728
2.3125,0.00302702
2.511719,0.00302702
3.0039065,0.00258213
3.796875,0.0021232
5.3828125,0.0016291
This graph shows average velocity vs. time interval, not average velocity vs. clock time. Your clock times run from 0 to thirty-some seconds.
** Your description of your graph of average velocity vs clock time: **
Negative slope that becomes more positive from left to right.
** Your explanation of how acceleration values were obtained: **
0.896
0.2557110
0.0167745
0.0066601
0.0056888
0.0052183
0.0049819
0.0043180
0.0037885
0.0035106
0.0023588
0.0028253
0.0023930
0.0019751
0.0017742
0.0016047
0.0013089
0.0012051
8.595E-4
5.5916E-4
3.0264847605224963715529753265602E-4
You don't explain how your acceleration values were determined. The values you show don't appear to be consistent with the velocities and time intervals you report.
** Your acceleration vs clock time table: **
0.0625000,0.896000
0.1523438,0.255711
0.5039063,0.016775
0.9609375,0.006660
1.1250000,0.005689
1.1601565,0.005218
1.2070315,0.004982
1.2968750,0.004318
1.3750000,0.003789
1.4179690,0.003511
1.4882815,0.002359
1.6015625,0.002825
1.6601565,0.002393
1.7578130,0.001975
1.9140630,0.001774
1.9960940,0.001605
2.1640625,0.001309
2.3125000,0.001205
2.5117190,0.000860
3.0039065,0.000559
3.7968750,0.000303
** According to the evidence here, is acceleration increasing, decreasing, staying the same or is in not possible to tell? **
My data indicates that the acceleration of the water surface is decreasing and I believe this is indeed what is happening.
See my notes and please submit a revision accordingly, indicating revisions and/or explanations and/or questions, as appropriate, by &&&&.