Physics 121
Laboratory Report
Experiment #6
Section EL
The Conservation of Mechanical Energy
Prepared by
Tingo Kanjadza
Lab Partners: Wehlie Gassim, Jacob Scott, Richard Ketiku, Julia Newnham, Jehlyn Soura
28 November 2023
Purpose:
In this study, our aim is to examine the preservation of mechanical energy as gravitational
potential energy undergoes transformation into kinetic energy.
Theory:
A virtually weightless string, spanning a weightless and frictionless pulley, links a
descending mass to a glider on a frictionless air track. As the weight descends (not in
free-fall), it induces acceleration in the glider along the air track. Within this dual-mass
system, an energy transition occurs from potential to kinetic. The descending weight
loses potential energy, while both the falling mass and the glider acquire energy.
If 'm' represents the mass of the descending weight, 'M' denotes the mass of the glider, 'v'
signifies the velocity of the system, and 'h' signifies the distance the weight has
descended, the overall mechanical energy is characterized by the equation.
1) TME = KE + PE
2) TME = 0.5(M + m)v2 + mgh
Method:
A spark tape, affixed to the air track in the customary fashion, is employed for motion
analysis. The glider is retracted, positioning the weight at its most convenient highest
point. Subsequently, upon release, the spark timer, configured to intervals of 1/40
seconds, documents the motion trajectory of the glider.
t (s)
v (m)
x (m)
0
0.025
0.05
0.075
0
0
𝛿v (m)
0
h (m)
𝛿h (m)
PE (J)
𝛿PE (J)
0.00000
0.00000
001414 4.66078 013859
1.146 213562
2 29291
KE (J)
𝛿KE (J) TME (J)
0.00112 4.66078
0 308019
2
1.132
4.60384
4
0.06507 1.75775 4.66891
2
6157
6
0.04
1.123
4.56724
1
0.04390 1.17113 4.61114
7
6078
8
0.4533 0.0266
0.034 33333 66667
1.112
4.52250
4
0.04264 0.79022 4.56514
3556
6556
7556
0.014
0.023
0.56
0.46
0.08
0.1
0.049
0.49
0.02
1.097
4.46149
9
0.04982 0.52029 4.51131
075
2539
975
0.125
0.067
0.536
0.016
1.079
4.38829
3
0.05961 0.35784 4.44790
392
9411
692
0.15
0
0.58
0.0133
33333
1.146
4.30695
3
0.06980 0.28137 4.37675
3
7257
6
0.6285 0.0114
0.11 71429 28571
1.036
4.21341
2
0.08198 0.19325 4.29539
3673
4631
5673
0.01
1.011
4.11173
7
0.09454 0.14828 4.20627
2188
9144
9188
0.7288 0.0088
0.164 88889 88889
0.982
3.99379
4
0.11024 0.11410 4.10403
0395
0248
4395
0.78
0.008
0.951
3.86771
7
0.12624 0.08983
3
7186 3.99396
0.275
0.8290 0.0072
0.228 90909 72727
0.918
3.73350
6
0.14263 0.07194 3.87613
3785
0737
9785
0.3
0.8833 0.0066
0.265 33333 66667
0.881
3.58302
7
0.16190 0.05755 3.74493
7639
0721
4639
0.325
0.9353 0.0061
0.304 84615 53846
0.842
3.42441
4
0.18155 0.04659 3.60596
0959
5682
4959
0.35
0.9885 0.0057
0.346 71429 14286
0.8
3.2536
0.20278 0.03783 3.45638
4245
8792
4245
1.0426 0.0053
66667 33333
0.755
3.07058
5
0.22558 0.03077 3.29616
4409
2104
9409
0.005
0.708
2.87943
6
0.24879 0.02513 3.12823
7688
9216
3688
1.1505 0.0047
0.489 88235 05882
0.657
2.67201
9
0.27469 0.02038 2.94671
9557
6722
8557
1.2044 0.0044
44444 44444
0.604
2.45646
8
0.30101 0.01652 2.75748
7432
9399
5432
1.2568 0.0042
0.597 42105 10526
0.549
2.23278
3
0.32777 1.34E-0 2.56056
7806
2
0806
1.312
0.004
0.49
1.99283
0.35717 1.06E-0 2.35000
888
2
888
0.525
1.3657 0.0038
0.717 14286 09524
0.429
1.74474
3
0.38702 8.34E-0 2.13176
3918
3
6918
0.55
0.0036
1.42 36364
0.365
1.48445
5
0.41840 6.39E-0 1.90285
3
3
8
0.175
0.2
0.225
0.25
0.135
0.195
0.375
0.391
0.4
0.438
0.425
0.45
0.475
0.5
0.542
0.656
0.781
0.675
1.095
0.575
1.4678 0.0034
0.844 26087 78261
0.302
1.22823
4
0.44706 4.81E-0 1.67529
1535
3
5535
0.6
1.5333 0.0033
0.92 33333 33333
0.226
0.91914
2
0.48785 3.23E-0 1.40699
5556
3
7556
0.625
0.993 1.5888 0.0032
0.153
0.62225
1
0.52378 1.99E-0 1.14604
9229
3
0229
0.65
1.6446 0.0030
1.069 15385 76923
0.077
0.31315
9
0.56123 9.17E-0 0.87439
7651
4
6651
1.6977 0.0029
77778 62963
0
0
0.675
t (s)
1.146
PE (J)
0
4.66078
2
KE (J)
0
TME (J)
4.66078
2
0.025
4.60384 0.06507 4.66891
4
2
6
0.05
4.56724 0.04390 4.61114
1
7
8
0.075
4.52250 0.04264 4.56514
4
3556
7556
0.1
4.46149 0.04982 4.51131
9
075
975
0.125
4.38829 0.05961 4.44790
3
392
692
0.15
4.30695 0.06980 4.37675
3
3
6
0.175
4.21341 0.08198 4.29539
2
3673
5673
4.11173 0.09454 4.20627
0.2
7
2188
9188
3.99379 0.11024 4.10403
0.225
4
0395
4395
3.86771 0.12624
0.25
7
3 3.99396
3.73350 0.14263 3.87613
0.275
6
3785
9785
0.3
3.58302 0.16190 3.74493
7
7639
4639
0.59810
8247
0
0.59810
8247
0.325
0.35
3.42441 0.18155 3.60596
4
0959
4959
3.2536
0.20278 3.45638
4245
4245
3.07058 0.22558 3.29616
0.375
5
4409
9409
2.87943 0.24879 3.12823
0.4
6
7688
3688
2.67201 0.27469 2.94671
0.425
9
9557
8557
2.45646 0.30101 2.75748
0.45
8
7432
5432
0.475
2.23278 0.32777 2.56056
3
7806
0806
0.5 1.99283
0.35717 2.35000
888
888
0.525
1.74474 0.38702 2.13176
3
3918
6918
0.55
1.48445 0.41840 1.90285
5
3
8
0.575
1.22823 0.44706 1.67529
4
1535
5535
0.6
0.91914 0.48785 1.40699
2
5556
7556
0.625
0.62225 0.52378 1.14604
1
9229
0229
0.65
0.31315 0.56123 0.87439
9
7651
6651
0.675
Graphs:
0
0.59810 0.59810
8247
8247
Questions:
1. While descending the hill, the skier experiences a reduction in potential energy and
a corresponding increase in kinetic energy. Upon reaching the bottom and coming to
a halt, the kinetic energy diminishes, while the potential energy remains constant.
2. While running, she elevates her potential energy, and upon embedding the pole into
the ground, this action transforms kinetic energy into potential energy associated
with the pole's height. This conversion leads to a surge in kinetic energy, propelling
her into the air.