Phy 202
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.? **
decrease as water flows from the cylinder
** Is the velocity of the water surface increasing, decreasing, etc.? **
with the buoy's weight pressing down on the water, I would think that the velocity of the water leaving the cylinder and the water surface would remain the same (constant); sort of like squeezing the air out of a child's water 'floaty', as long as the pressure that you exert squeezing the 'floaty' remains constant the velocity of the air leaving it will remain constant
** 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? **
we could time the water as it leaves the cylinder from a 'start point' to an 'end point'; we could find the volume of the liquid in the cylinder; more importantly I think, is that the velocity of the water surface and the velocity of the water exiting the cylinder should be the same, so if we find the velocity of one we would have the velocity of the other
** Explain how we know that a change in velocity implies the action of a force: **
if floating in space, your velocity would remain constant. The only way to stop or go faster is for there to be something out there to either hold you back or give you an extra push. If the cylinder is plugged, then the liquid is contained within it because the force pushing down on the water has an equal opposing force pushing back up. By unplugging the cylinder, the liquid escapes and is being pushed by the force from on top. The heavier the force the faster the liquid will leave the cylinder.
** Does the depth seem to be changing at a regular rate, at a faster and faster rate, or at a slower and slower rate **
slower at slower rate.
the weight of the liquid pushing down on the hole at the bottom gets less as time goes on.
** What do you think a graph of depth vs. time would look like? **
I think it would start out pretty steep and then curve as the time goes on
** 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? **
decrease
** Does this distance change at an increasing, decreasing or steady rate? **
increasing
** What do you think a graph of this horizontal distance vs. time would look like? **
the graph would resemble the first hill on a roller coaster, getting steeper as time goes on
** The contents of TIMER program as you submitted them: **
1 8994.336 8994.336
2 8995.473 1.136719
3 8996.523 1.050781
4 8997.793 1.269531
5 8999.113 1.320313
6 9000.367 1.253906
7 9001.688 1.320313
8 9003.082 1.394531
9 9004.473 1.390625
10 9005.969 1.496094
11 9007.695 1.726563
12 9009.391 1.695313
13 9011.09 1.699219
14 9013.113 2.023438
15 9014.969 1.855469
16 9016.887 1.917969
17 9019.023 2.136719
18 9021.855 2.832031
19 9024.758 2.902344
20 9027.648 2.890625
21 9032.441 4.792969
22 9038.613 6.171875
** The vertical positions of the large marks as you reported them, relative to the center of the outflow hole **
.7 cm
1.5 cm
2.3 cm
3.1 cm
3.9 cm
4.7 cm
5.5 cm
6.3 cm
7.1 cm
7.9 cm
8.7 cm
9.5 cm
10.3 cm
11.1 cm
11.9 cm
12.7 cm
13.5 cm
14.3 cm
15.1 cm
15.9 cm
16.7 cm
17.5 cm
** Your table for depth (in cm) vs clock time (in seconds) **
0, 17.5
1.14, 16.7
2.19, 15.9
3.46, 15.1
4.78, 14.3
6.03, 13.5
7.35, 12.7
8.74, 11.9
10.1, 11.1
11.6, 10.3
13.4, 9.50
15.1, 8.70
17.1, 7.90
19.1, 7.10
20.9, 6.30
22.9, 5.50
25.0, 4.70
27.8, 3.90
30.7, 3.10
33.6, 2.30
38.4, 1.50
44.6, 0.70
** Is the depth changing at a regular rate, at a faster and faster rate, or at a slower and slower rate? **
I believe my data supports my previous answers;
the depth appears to be changing slower at a slower rate
** Your description of your depth vs. t graph: **
my graph goes down and to the right;
it appears that the graph of depth vs. clock time shows a fairly constant fluid flow
** Your explanation and list of average average velocities: **
.70 cm/s
.76 cm/s
.63 cm/s
.61 cm/s
.64 cm/s
.61 cm/s
.58 cm/s
.58 cm/s
.53 cm/s
.46 cm/s
.47 cm/s
.40 cm/s
.40 cm/s
.43 cm/s
.42 cm/s
.37 cm/s
.28 cm/s
.28 cm/s
.28 cm/s
.17 cm/s
.13 cm/s
average velocities were found by taking the difference between two consecutive heights and dividing that by the difference between two consecutive time intervals : (1.5 - .7) / (44.58 - 38.41) = .13 cm/s
** The midpoints of your time intervals and how you obtained them: **
.570
1.665
2.825
4.120
5.405
6.690
8.045
9.420
10.85
12.50
14.25
16.10
18.10
20.00
21.90
23.95
26.40
29.25
32.15
36.00
41.50
I found the difference between two consecutive clock times, and then divided that by 2, and then added that to the smallest of the two clock times : 44.6 - 38.4 = 6.2 / 2 = 3.1 + 38.4 = 41.5
** Your table of average velocity of water surface vs. clock time: **
0.570, .70
1.665, .76
2.825, .63
4.120, .61
5.405, .64
6.690, .61
8.045, .58
9.420, .58
10.85, .53
12.50, .46
14.25, .47
16.10, .40
18.10, .40
20.00, .43
21.90, .42
23.95, .37
26.40, .28
29.25, .28
32.15, .28
36.00, .17
41.50, .13
** Your description of your graph of average velocity vs clock time: **
my graph goes down and to the right, however, it goes up and down all the way to the end; just like the stock market
** Your explanation of how acceleration values were obtained: **
my numbers are coming out too large;
I'm going to haveto meditate on this one
your calculations for acceleration would be the same as those you would perform to do difference quotients on your preceding set of velocities vs. clock times
** Your acceleration vs clock time table: **
see above
** According to the evidence here, is acceleration increasing, decreasing, staying the same or is in not possible to tell? **
see above
** **
1 hour 25 minutes
Good responses. See my notes and let me know if you have questions.