flow experiment_data

Your initial message (if any):

Is flow rate increasing, decreasing, etc.?

I would expect the rate of flow to decrease the as the water flows from the cylinder, unless the size of the hole is changed.

Is the velocity of the water surface increasing, decreasing, etc.?

The pressure or the weight of the water pushing it out of the hole. The further down the less weight and pressure.

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 bigger the hole in the cylinder the faster water surface would go down. The greater the diameter of the cylinder the slower the water surface would move. You could determine the velocity of the water surface by measuring the time it took to reach equal markers on the graduated cylinders. E.g. measuring how long it took every 10 ml. Then determine the rate.

Explain how we know that a change in velocity implies the action of a force:

Their is the force of the water pushing down on itself. The more water the faster the water would exit.

Does the depth seem to be changing at a regular rate, at a faster and faster rate, or at a slower and slower rate

From the pictures one can see that the water is being pushed out further when the cylinder is nearly full. When half full the water is being pushed out about half as far, and when near empty the water is barely being pushed out of the cylinder. Depth seems to be changing at a slower and slower rate. This is evident by the amount of fluid coming out in the picture with the least amount of water in the cylinder. If less is coming out the depth is changing slower and slower.

What do you think a graph of depth vs. time would look like?

The depth would be decreasing 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?

The horizontal distance decreases as time goes on.

Does this distance change at an increasing, decreasing or steady rate?

It appears to be decreasing at a steady rate.

What do you think a graph of this horizontal distance vs. time would look like?

It appears to be decreasing at an decresing.

The contents of TIMER program as you submitted them:

1 151.0156 151.0156

2 153.4063 2.390625

3 155.4688 2.0625

4 157.4688 2

5 159.4844 2.015625

6 161.6719 2.1875

7 164.5469 2.875

8 167.1875 2.640625

9 170.25 3.0625

10 173.625 3.375

11 178.1563 4.53125

12 184.2813 6.125

13 192.4219 8.140625

The vertical positions of the large marks as you reported them, relative to the center of the outflow hole

2.40

4.35

6.30

8.25

10.20

12.15

14.10

16.05

18.00

19.95

21.90

23.85

Your table for depth (in cm) vs clock time (in seconds)

0, 8.14

2.40, 6.13

4.35, 4.53

6.30, 3.38

8.25, 3.06

10.20, 2.64

12.15, 2.88

14.10, 2.19

16.05, 2.02

18.00, 2.00

19.95, 2.06

21.90, 2.30

23.85, 0

Is the depth changing at a regular rate, at a faster and faster rate, or at a slower and slower rate?

Yes, it supports my answers above. The depth is changing at a slower rate. The further down the depth got the slower the depth decreased.

Your description of your depth vs. t graph:

The graph is decreasing at a decreasing rate. It starts off at steeper slope than it finishes.

Your explanation and list of average average velocities:

To find the average velocity I divided the number of cm between each marker by the time it took to get to that marker. I divided the cm by the time in seconds. Starting with the least depth, the average velocity per time interval were as follows (all are in cm/s):

.295

.318

.430

.577

.637

.739

.677

.890

.965

.947

.816

The midpoints of your time intervals and how you obtained them:

The time intervals begin with the smallest depth first. They were obtained by taking the time interval and dividing it by two.

4.07

3.065

2.27

1.69

1.53

1.32

1.44

1.095

1.01

1.00

1.03

1.195

Your table of average velocity of water surface vs. clock time:

.295, 4.07

.318, 3.07

.430, 2.27

.577, 1.69

.637, 1.53

.739, 1.32

.677, 1.44

.890, 1.095

.965, 1.01

.965, 1.00

.947, 1.03

.816, 1.195

Your description of your graph of average velocity vs clock time:

The graph is decreasing at a decreasing rate. This means that the velocity is increases clock time decreases.

Your explanation of how acceleration values were obtained:

acceleration is change in velocity divided by time. To solve this I subtracted the change in velocites between each marker and divided them by the time between the two. All are in cm/s^2.

.0028

.018

.032

.018

.019

.024

.074

.034

.009

.064

.34

Your acceleration vs clock time table:

4.07, .0028

3.065, .018

2.265, .032

1.69, .018

1.53, .019

1.32, .024

1.44, .074

1.095, .034

1.01, 0

1.0, .009

1.03, .064

1.195, .34

According to the evidence here, is acceleration increasing, decreasing, staying the same or is in not possible to tell?

It is a little difficult to tell from the data. I would say that the acceleration of the water surface is fairly constant from the data, but I think that the acceleration is decreasing. 13:04:16 01-29-2006