Exp.
7 Determination of moment of inertia of
rigid bodies
I Experimental objectives
I. Learn to use moment of inertia instrument, measure the moment of inertia of regular
rigid body and compare with theoretical value;
2. Verify the parallel-axis theorem with experiment.
II Experimental instrument
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III Experimental principle
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IV The procedures of the experiment
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V Data processing
1 . Measure the moment of inertia of aluminum ring
Mass of the aluminum ring M = 4:?iA 5 'bMass of the weight ( including hook ) m=5..k.,5 ~
r= ~- ?0 0w\ N1= Q.
- N2 = !Q g= -:l
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Rotary
Times
system t1(s) t2(s) p(s-2 ) t ul (s) t u2 (s) P. (s-2)
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1 J 6b A '.3 .3<?,h 2.o~3 o.s 6':( ,A.'101 -o.ob~ 3
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object stage
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2• Verify parallel-axis theorem
The mass ofone pillar M= A6S bo..
·o The mass of the weight ( including hook) m= '5 y . '.o ~
d= 3,oo (ml 2Md2= 2 ~~ .\o\.~~
0 N,= -<
0 N2= b
Under the action of M Under the action of Mu
Times p)s-2)
t 1(s) t2 (s) p(s-2) t,, 1(s) t,, 2(s)
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'4
VI Discussion
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Initial data (the data recorded in class)
Under the action of M unde r the action of Mu
Rotary system
Time{s) t1 t2 13 (s- 2) tu! tu2 f3 u (s -2)
1 1.661 3.394 2.0428 0.567 1.707 -0.06 8334
The objec t 2 1.456 3.125 2.0559 0.564 1.698 -0.069427
stage 3 1.484 3.16 2.0647 0.567 1.707 -0.06 8334
avera ge 2.0545 -0.068699
1 2.03 4.335 1.0873 0.778 2.344 -0.044003
The whole 2 1.847 4.084 1.0851 0.785 2.364 -0.03 8597
system{J) 3 1.919 4.189 1.0798 0.769 2.316 -0.041048
avera ge 1.084 -0.04 1216
Under the action of M unde r the action of Mu
Time{s) t1 t2 13 (s -2) tul t u2 13 u(s- 2)
1 1.683 3.602 1.5631 0.653 1.967 -0.05 9564
33'{J 1) 2 1.696 3.616 1.5709 0.652 1.967 -0.08 1964
3 1.735 3.661 1.586 0.666 2.009 -0.07 6926
avera ge 1.5733 -0.07 2818
1 1.913 3.924 1.5109 0.654 1.986 -0.17 4325
15'{J 2) 2 1.536 3.418 1.5135 0.659 1.987 -0.07 2265
3 1.617 3.539 1.499 0.658 1.985 -0.07 9753
avera ge 1.5078 -0.10 8781
