In: Physics
can you explain 3 and 4
For Questions 1-3, Two different groups are measuring the SAME cart travelling with a constant velocity on a straight track. Table 1 and Table 2 represent the data collected by each group. | |||||||||||
Table 1 | 1. Use the standard "Kinematics Equations" for velocity and acceleration to find these values for each time step in Table 1 and Table 2 as well as their average and uncertainty. Definitely take advantage of Excel's "Copy" and "Paste" functions so you only need to type equations once or twice. Give special attention to the cells on the edge of the data set. | ||||||||||
Average Velocity: | Average Acceleration: | ||||||||||
Velocity Uncertainty: | 0.575694444 | Acceleration Uncertainty: | 0.09296875 | ||||||||
Time (s) | Position (cm) | Velocity (cm/s) | Acceleration (cm/s/s) | ||||||||
0 | 0 | ||||||||||
1 | 14.875 | 12.05 | |||||||||
2 | 24.1 | 13.3625 | 1.06875 | 2. Use proper rounding techniques to report the velocity and acceleration of the cart for each data table. (Note, because the data updates every time you edit this sheet, the instructor is aware that there might be a slight mismatch between your reported value and data showing at the time of submission.) | |||||||
3 | 41.6 | 14.1875 | 0.027083333 | ||||||||
4 | 52.475 | 13.0375 | 0.098863636 | ||||||||
5 | 67.675 | 13.1 | 0.16625 | ||||||||
6 | 78.675 | 11.375 | 0.095833333 | ||||||||
7 | 90.425 | 12.2375 | -0.2125 | ||||||||
8 | 103.15 | 13.075 | -0.414285714 | Table 1: Velocity = | |||||||
9 | 116.575 | 15.1375 | -0.15 | ||||||||
10 | 133.425 | 13.975 | 0.3275 | Table 2: Velocity = | |||||||
11 | 144.525 | 13.5 | 0.20625 | ||||||||
12 | 160.425 | 13.15 | 0.141666667 | Table 1: Acceleration = | |||||||
13 | 170.825 | 13.075 | -0.8 | ||||||||
14 | 186.575 | 14.75 | 0.8875 | Table 2: Acceleration = | |||||||
15 | 200.325 | 12.1875 | #DIV/0! | ||||||||
16 | 210.95 | 11.8125 | 1.15 | 3. Are your results consistent with the description given above: "Two different groups are measuring the same cart travelling with constant velocity on a straight track." Explain any numerical inconsistencies that are in the data using your understanding of "Uncertainty". | |||||||
17 | 223.95 | 13.3375 | 1.15625 | ||||||||
18 | 237.625 | 14.125 | -0.04537037 | ||||||||
19 | 252.2 | 13.20138889 | 0.8828125 | ||||||||
Table 2 | |||||||||||
Average Velocity | Average Acceleration: | ||||||||||
velocity uncertainty: | 4.611111111 | Acceleration Uncertainty: | 14.77083333 | ||||||||
Time (s) | Position (cm) | Velocity (cm/s) | Acceleration (cm/s/s) | ||||||||
0 | 0 | ||||||||||
0.1 | 2.02 | 4.325 | |||||||||
0.2 | 0.865 | 18.325 | 38.75 | ||||||||
0.3 | 5.685 | 12.075 | -66.25 | 4. Compare and contrast the uncertainties measured by these two groups. Fundamentally what caused one group to get more precise data than another? | |||||||
0.4 | 3.28 | 5.075 | 110 | ||||||||
0.5 | 6.7 | 34.075 | 38.125 | ||||||||
0.6 | 10.095 | 12.7 | -195.625 | ||||||||
0.7 | 9.24 | -5.05 | 57.5 | ||||||||
0.8 | 9.085 | 24.2 | 182.5 | ||||||||
0.9 | 14.08 | 31.45 | -60.625 | ||||||||
1 | 15.375 | 12.075 | -194.375 | ||||||||
1.1 | 16.495 | -7.425 | -100.625 | ||||||||
1.2 | 13.89 | -8.05 | 106.875 | ||||||||
1.3 | 14.885 | 13.95 | 217.5 | ||||||||
1.4 | 16.68 | 35.45 | -0.625 | ||||||||
1.5 | 21.975 | 13.825 | -138.125 | ||||||||
1.6 | 19.445 | 7.825 | 54.375 | ||||||||
1.7 | 23.54 | 24.7 | 43.75 | ||||||||
1.8 | 24.385 | 16.575 | -55.76388889 | ||||||||
1.9 | 26.855 | 13.54722222 | 9.208333333 |
3. Explanation of numerical inconsistency in the data which is
measured by two different groups of the same cart moving with a
constant velocity is as follows: The data inconsistency may arise
due to the change in reference frames of the two groups. For
example, the first group measures the uncertainty in velocity to be
0.575...
, and the other group measures it to be 4.611....
.
In the same way, uncertainty in acceleration of the cart comes out
to be 0.0929...
which is very less as compared to the uncertainty measured by the
Group 2, i.e. 14.7708....
.We
see that the uncertainity in velocity/acceleration in case of Group
1 is less whereas, the second group found more uncertainty. That
means the first group readings are more precise than the second
group readings. Less is the uncertainty, more is the precision.
4. The fundamental reason behind one group getting more precise
data than the other group is that change in time interval,
and also the variation in total time for which the readings are
taken. Group 1 took readings of acceleration and velocity after
each second upto 19 seconds whereas, Group 2 took readings after
every 0.1 second interval upto only 2 seconds. This variation in
the time interval is the cause behind getting less precise data in
case of Group 2. Readings are concentratedover a very small
interval of 2 seconds, i.e. only from t=0 sec to t=2 sec with
=0.1 sec. In case of Group 1, readings are spread over a time
interval of 19 seconds, i.e. t=0 sec to t=19 sec, with
=1 sec.