lnf?lna?lnb?ln?a?b?dff?daa?dbbba?a?b?ba?a?b?A2?B24A?d?a?b?a?ba?daa?dbb?daa?b?dba?b ??da?b?a?b?adb(注意:合并相同微分项)
误差传递公式:?ff??a?b?a?b??b(5)f?;
lnf?ln?A2?B2??lnA?ln4
dff?dA?BA?BA?B2?2222??dAA?2AA?B2B22dA?2BA?B22dB?dAA
22 =
AA?B?2?dA?A?B22dB
误差传递公式:
?ffA?B222 ?AA?B2?2??A?2BA?B22?B
(6)I2?r2??I1??;
?r1?lnI2?lnI1?2lnr2?2lnr1dI2I2?I2I2?dI1I1?I1I1?2dr2r2?r2r2?2dr1r1?r1r1
误差传递公式:??2?2
(7)V0?V1??t,?为常量;
lnV0?lnV?dV0?dVV?12ln?1??t??2(1??t) V0?V0V0dt
误差传递公式:??VV??2(1??t)?t(8)n?sinisinr。
lnn?lnsini?lnsin?dnn?cosisinidi?cos?sin?d?
误差传递公式:?nn?coti?i?coti??
方和根合成法,记住公式,掌握偏微分即可
7、解 (1)
?L?b?1,
?L?d2?12
2SL???L???L?22S???b??Sd???b???d?Sb?214Sd
2(2)
lnL0?lnL?ln?1??t?
?lnL0?LSL0L0?1L,
2?lnL0?t??1??t2
22???lnL0???lnL0?22??SL???St???L???t?12??St??SL?? ????L1??t????(3)
lnv??lnv?m(lnm?lng?lnl0?lnm0)?ln2?lnL 12m?,
?lnv?l0?12l0,
?lnv?m0??12m0,
?lnv?L??1L
Svv???lnv?2??lnv??Sm????l?m??0?2?2??lnv?Sl?????m00??2?2??lnv?2?Sm???SL?0?L???22
??Sl0?Sm??????2l?2m??02??S??S????m???L???2m??L??2228、解
(1)
N?A?B??84.56cm131313C?0.5768?85.07?13?3.247?0.58?85.07?1.082
?N??A??B??C?0.0002?0.02??0.002?0.03cm
测量结果:
N?N??N?(84.56?0.03)cm (2) 设y?y?1V1V?
1?0.001000cm?21000
?2?y??VV2?110002?1?10?6cm
测量结果:
y?y??y?0.001000?0.000001?(1.000?0.001)?10?3cm?2
(3) R?abx?13.6510.871?67.0?84.14?
ER??RR??aa??bb??xx?0.0213.65?0.00510.871?0.867.0
=0.0015+0.0005+0.01=0.012 ?R?RER?84.14?0.012?1?
测量结果: R?R??R?(84?1)?
9、解:
d?1nn
?i?1di?1n110(14.298?14.256???14.216)?14.261mm
2iSd???d??n?1i?1?110?1??14.298?14.261?2???14.256?14.261?????14.216?14.26122? =0.02mm
S仪??仪3?0.0043?0.002mm
与仪器误差合成 ??Sd?S仪?220.02?0.00222?0.02mm测量结果d?d???(14.26?0.02)mm
10、解:
g?4?lT22
2g?4?lT22?4?3.1415?98.8121.98422?990.75cm?s2?2
2Eg??Ugg??Ul??2UT????????l??T??82?0.02??2?0.0002??????98.811.9842????
0.0002?4?10?0.014?2Ug?g?Eg?990.81?0.014?1?10cm?s测量结果g?g?Ug?(9.9?0.1)?10cm?s2?2