Materials:
air table -weight spark timer -timer pedal string -air puck white paper -air pump pulley -carbon paper
Procedure:
1) First, set up air table which is shown in figure 1 on page 3. Plug in the air pump and turn on spark timer.
2) Place a sheet of white carbon paper, diagonally, so that the top and bottom of the paper are lined up.
3) Place the air puck on the top corner of the carbon paper. Making sure not to move the air puck, release the puck while simultaneously holding down the timer pedal allowing the weight and pulley pull the puck to the bottom of the paper. Release the timer pedal as soon as the air puck has stopped moving.
4) Examine 26 dots created on the carbon paper. The dots should be in a straight line, increasingly becoming further apart from each other.
Figure 1 Arrangement of materials used for the experiment
Observations:
The spark timer was set to 50Hz, this created a time interval of = 0.02s between each dot. The dots created by the air table can be found in figure 2 on page 3. Measurements of position can be found in table 1 on page 4. Figure 3 on page 5 contains a position versus time graph for the air puck. A curve of best fit has been drawn though the graph. Figure 4 on page 6 contains a velocity versus time graph for the air puck. A line of best fit has been drawn though the graph.
Dot Number
Time (s)
Position
(cm[f])
Displacement (cm[f])
Velocity (cm/s[f])
Time for Velocity Graph (s)
1
0.00
0.00
-
-
-
2
0.02
0.44
0.44
22.0
0.01
3
0.04
1.13
0.69
34.5
0.03
4
0.06
1.69
0.56
28.0
0.05
5
0.08
2.45
0.76
38.0
0.07
6
0.10
3.36
0.91
45.5
0.09
7
0.12
4.18
0.82
41.0
0.11
8
0.14
5.09
0.91
45.5
0.13
9
0.16
6.03
0.94
47.0
0.15
10
0.18
7.01
0.98
49.0
0.17
11
0.20
8.04
1.03
51.5
0.19
12
0.22
9.19
1.15
57.5
0.21
13
0.24
10.37
1.18
59.0
0.23
14
0.26
11.68
1.31
65.5
0.25
15
0.28
12.99
1.31
65.5
0.27
16
0.30
14.25
1.26
63.0
0.29
17
0.32
15.61
1.36
68.0
0.31
18
0.34
17.08
1.47
73.5
0.33
19
0.36
18.71
1.63
81.5
0.35
20
0.38
20.32
1.61
80.5
0.37
21
0.40
21.85
1.53
76.5
0.39
22
0.42
23.55
1.70
85.0
0.41
23
0.44
25.19
1.64
82.0
0.43
24
0.46
27.07
1.88
94.0
0.45
25
0.48
28.82
1.75
87.5
0.47
26
0.50
30.59
1.77
88.5
0.49
Table 1 The data calculated shows how far apart the dots are and the displacement between them. The table also shows the instantaneous velocity of the air puck at each dot.
The following is a sample calculation of the displacement of the air puck for the interval from 0.20s to 0.22s, as seen in the eleventh row of Table 1 on page 4.
= 1.15cm[f]
Therefore the displacement of the puck was 1.15cm[f]. The remainder of the displacement values can be found in Table 1 on page 2.
The following is a sample calculation of the velocity of