复摆实验报告
一、实验数据
复摆质量m=396.71 g
复摆重心位置H G=0.00 cm
铜刀口质量m′=6.30 g
表1 数据记录、计算与列表
h/cm 20T/s T/s h2/m2 T2|h|/(s2m)
28.16 25.0594 1.25297 0.07929856 0.442093364
27.16 24.8624 1.24312 0.07376656 0.419716336
26.12 24.6864 1.23432 0.06822544 0.397950179
25.16 24.5101 1.225505 0.06330256 0.377868606
24.12 24.3415 1.217075 0.05817744 0.357282699
23.12 24.1924 1.20962 0.05345344 0.338287342
22.14 24.0407 1.202035 0.04901796 0.319898234
21.16 23.9264 1.19632 0.04477456 0.302838014
20.14 23.8218 1.19109 0.04056196 0.285725251
19.14 23.7382 1.18691 0.03663396 0.269635774
18.16 23.7012 1.18506 0.03297856 0.255033084
17.14 23.6818 1.18409 0.02937796 0.240314649
16.16 23.72 1.186 0.02611456 0.227305914
15.18 23.7819 1.189095 0.02304324 0.214637142
14.16 23.9204 1.19602 0.02005056 0.20255368
13.16 24.1304 1.20652 0.01731856 0.191568871
12.16 24.4062 1.22031 0.01478656 0.18108143
11.14 24.7928 1.23964 0.01240996 0.171189197
10.14 25.319 1.26595 0.01028196 0.162506621
8.16 26.8804 1.34402 0.00665856 0.147401404
6.16 29.6492 1.48246 0.00379456 0.135377559
4.12 34.6873 1.734365 0.00169744 0.123930504
2.18 46.7125 2.335625 0.00047524 0.118922142
1.12 61.3588 3.06794 0.00012544 0.105417265
-28.28 25.0597 1.252985 0.07997584 0.443987915
-27.28 24.8769 1.243845 0.07441984 0.422062625
-26.26 24.6732 1.23366 0.06895876 0.399655403
-25.28 24.4948 1.22474 0.06390784 0.379196983
-24.28 24.3283 1.216415 0.05895184 0.359262772 -23.28 24.1769 1.208845 0.05419584 0.340192091 -22.29 24.0344 1.20172 0.04968441 0.321896791 -21.28 23.9301 1.196505 0.04528384 0.304649633 -20.28 23.8118 1.19059 0.04112784 0.287469922 -19.29 23.749 1.18745 0.03721041 0.271996234 -18.28 23.71
1.1855
0.03341584
0.256908994 -17.29 23.6919 1.184595 0.02989441 0.242624573 -16.28 23.7116 1.18558 0.02650384 0.22883167 -15.29 23.7244 1.18622 0.02337841 0.215148325 -14.29 23.9142 1.19571 0.02042041 0.204307332 -13.28 24.1227 1.206135 0.01763584 0.193192346 -12.28 24.4301 1.221505 0.01507984 0.183226744 -11.29 24.7789 1.238945 0.01274641 0.173299774 -10.28 25.301
1.26505 0.01056784
0.164516134 -9.29 25.9778 1.29889 0.00863041 0.156733005 -7.29 27.3267 1.366335 0.00531441 0.13609492 -5.29 31.8271 1.591355 0.00279841 0.133964528 -3.29 39.3259 1.966295 0.00108241 0.127201797 -1.28
61.9938 3.09969 0.00016384
0.1229834
法一:直线拟合
分别对左半部分和右半部分的T 2h-h 2关系作图,剔除无效数据,做线性拟合。
左半部分如图1所示:
斜率k 1=4.1123 s 2/m ,截距b 1=0.1182 s 2m ,相关系数R 12=0.999 计算得:
2
1
2
1/600.94)1(g s
m k ==π
右半部分如图2 所示:
斜率k 2=4.037s 2/m ,截距b 2=0.1215s 2m ,相关系数R 22=0.9998 计算得:
22
2
2/779.94)2(g s m k ==π
对以上两次测量求得的g 做加权平均,权重比正比于1
2)-1-R (,得:
2
2
22112112
21/749.9)
1()1()2()1()1()1(g s m R R g R g R =-+--+-=
复摆对重心的转动惯量:
3
2
110994.24b )1(-⨯==
π
G I 3
2
210078.34b )2(-⨯==
π
G I 3
2
221212
2G
10064.3)
1()1()2()1()1()1(I -⨯=-+--+-=R R I R I R G G 310779.2m
-⨯==
G
G I R 法二:近似共轭点法
T-h 关系如图3所示,在图中选择三组近似共轭点,选点具体信息如表2所示:
表2 共轭点选取
所以,
22/737.93
658
.9690.9864.9g s m =++=
法三:共轭点法
从图4上读出T=1.22000 s 除的两对共轭点的横坐标(见表3)
表3 T=1.22000处两对共轭点位置
cm 73.362
2
1=+=
L L L 22
23/742.94g s m T
L ==π。