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 is expected to decrease due to a decrease in the mass above the water forcing it out of the hole. As the water flows out the overall volume and mass decreases so there is less force pushing the water down and out of the tube.
** Is the velocity of the water surface increasing, decreasing, etc.? **
remain the same.
** 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? **
The greater the diameter of the hole the greater the velocity of the water surface. Also, the greater the diameter of the cylinder, the less the velocity of the water surface.
** Explain how we know that a change in velocity implies the action of a force: **
F=ma
If the water exiting has been accelerated, and the mass must stay constant, then we know that a force is involved.
** Does the depth seem to be changing at a regular rate, at a faster and faster rate, or at a slower and slower rate **
Seems to be changing at a regular rate. If the pictures were clearer We would be able to measure the volume in the cylinder vs. time, and calucated the change in depth.
** What do you think a graph of depth vs. time would look like? **
As time increases depth decreases at a decreasing rate.
** 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? **
decreases as time goes on
** Does this distance change at an increasing, decreasing or steady rate? **
Theres no way to know for sure, but looks as if it is changing at a steady rate.
** What do you think a graph of this horizontal distance vs. time would look like? **
as time increases the distance decreases at a decreasing rate.
** The contents of TIMER program as you submitted them: **
1 19.54688 19.54688
2 23.79688 3.84375
3 27.64063 4.25
4 34.20313 4.5625
5 38.8125 4.609375
6 43.03125 4.81875
7 48.07813 5.046875
8 52.82813 5.203125
** The vertical positions of the large marks as you reported them, relative to the center of the outflow hole **
3.3
6.6
9.9
13.2
16.4
19.7
23.0
26.3
** Your table for depth (in cm) vs clock time (in seconds) **
0, 26.3
3.84, 23.0
8.01, 19.7
12.5, 16.4
17.1, 13.2
21.9, 9.9
26.9, 6.6
30.8, 3.3
** Is the depth changing at a regular rate, at a faster and faster rate, or at a slower and slower rate? **
No its not. THe depth is changing at a slower and slower rate.
** Your description of your depth vs. t graph: **
My graph decreases at a decreasing rate as time increases.
** Your explanation and list of average average velocities: **
'ds=Vave 'dt
using this formula I calculated the average velocity of the waters surface.
0
5.99
2.46
1.32
.77
.45
.25
.11
** The midpoints of your time intervals and how you obtained them: **
0,
1.92
4.00
6.25
8.55
10.95
13.45
15.4
** Your table of average velocity of water surface vs. clock time: **
0 0
1.92 5.99
4 2.46
6.25 1.32
8.55 0.77
10.95 0.45
13.45 0.25
15.4 0.11
** Your description of your graph of average velocity vs clock time: **
my graph is decreasing at a decreasing rate.
** Your explanation of how acceleration values were obtained: **
Aave='dv/'dt
0
3.119791667
0.615
0.2112
0.09005848
0.04109589
0.018587361
0.007142857
** Your acceleration vs clock time table: **
0 0
1.92 3.12
4 0.615
6.25 0.2112
8.55 0.090058
10.95 0.041096
13.45 0.01858
15.4 0.007143
** According to the evidence here, is acceleration increasing, decreasing, staying the same or is in not possible to tell? **
Graphing this data, it seems that my acceleration is also decreasing. My guess is that the acceleration of the water surface is decreasing, based on all the calculations and my numerous graphs
** **
2 hrs
Very good work.
Note that the decreasing horizontal range of the exit stream is evidence that the depth changes at a decreasing rate. Whether the velocity of the water surface changes at a constant, increasing or decreasing rate can't be inferred from just the decreasing range of the exit stream. However the rate at which the range of the exit stream changes (for which we did not take data in this experiment) would tell us.