转动惯量不确定度计算公式 弹性系数K [1 Determination of K 2 We get T=4 K K Thus K=4 Uncertainty of k u(K) u(lpo) T-t K T2 1(x2-)-0)+7)&(r2)=27×u(T) Since we measure the time of 10 periods, so for each period, we have 1=.4 and ()=√ln2(1)+n2(t1) (T)=D4().Whe()=,(-4)2 n(n-1) 0.01 lB2(1 √33 2. Uncertainty of different objects l1 Plastic cylinder: u(D) 2× u( A(D)+B2(D) u(m)=√lx2(m)+an2(m) Whe n(m)=d=0.1g u(D) n(n-1) a0.2 g a0.002 √33 12 Metal b &l(l) u(K)「u(x2-n2 KII-1 转动惯量不确定度计算公式: 1. 弹性系数 K [1] Determination of K. From 0 0 2 I T K & 0 1 2 PC I I T K We get 2 2 0 0 4 I T K & 2 2 0 1 4 PC I I T K Thus 2 2 2 1 0 4 PC I K T T [2] Uncertainty of K. 2 2 2 2 1 0 2 2 1 0 ( ) ( ) ( ) PC PC u I u T T u K K I T T . Please note: 2 2 2 2 2 2 1 0 1 0 u T T u T u T ( ) [ ( )] [ ( )] & 2 1 1 1 u T T u T ( ) 2 ( ) . Since we measure the time of 10 periods, so for each period, we have 1 1 1 10 T t and 1 1 1 ( ) ( ) 10 u T u t . Where, 2 2 1 1 2 1 2 1 1 1 2 1 ( ) ( ) ( ) ( ) ( ) ( 1) 0.01 ( ) 3 3 A B i A B u t u t u t t t u t n n a u t s . 2. Uncertainty of different objects: [1] Plastic cylinder: 1 1 2 2 2 8 PC I mr mD & 2 2 ( ) (D) ( ) 2 PC PC u m u u I I m D Where, 1 2 2 2 1 2 ( ) ( ) ( ) ( ) 0.1 0.2 ( ) 3 3 B B B B u m u m u m u m d g a u m g & 2 2 2 2 2 ( ) ( ) ( ) ( ) ( ) ( 1) 0.002 ( ) 3 3 A B i A B u D u D u D D D u D n n a u D cm . [2] Metal barrel: 2 2 1 0 2 ( ) 4 MB K T T I & 2 2 2 2 1 0 2 2 1 0 ( ) ( ) ( ) MB MB u K u T T u I I K T T