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5.1 ????
5.2?????????
5.3???????
5.4?????????
5.5????
5.6?????
5.7???
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?1? ????
1. ????6?12????A?C?????????????v??????B?D???
??????????v?????
B
C
v1
2. ??????????????180??????10s???????30???????
???6?13???
3. ????6?14???AB???????BC???????CD??????? ?2? ?????????
1. ??????????????vx?800cos60?400m/s;????????????vy?
800sin60?692m/s???6?15?
vv
v
x
2. ???????????????????v2??????????????v1????
?v?v2?v1???????6?15
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??6.4m/s????
????????tan??0.8???38.7
3. ???????????6?16????????????????????v1????
????v?v1???????v2?????????????v2??????? 4. ????6?17????3? ???????
1. ???1???????????????????????????y?1.5m?gt2
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???t?
??0.55s???????x?vt?400.55m?22m?20m???????????????????????????????????????????
?????2????????????????vy?gt?9.80.55m/s?5.39m/s???????????????vx?v?40m/s????????
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v??/s?40.36m/s ?????????????????
???tan??vx?vy?405.39?7.42
2. ?????????????????????????y?2.45m?gt2
2
????
t?
??0.71s ????????x?vt?13.3m??????????????v?x?t?13.3?0.71m/s?18.7m/s?67.4km/h?60km/h????????? ???1????????????A?????????????????P??????????x????????????P???????????????????y???
?????????v? ?4? ?????????
2
1. ??????????????????
?1????????????????????????????????????y??2????????????A??????
?3????????????
P1?????????x1?
?4????????????????????????????????????4y??5????????????A??????
?6????????????P2?????????x2?
?7???x1?x2??2x1?x2???????????????????
????????????x????????????????y??2x1?x2??4y1?y2??????????????????? ?5? ????
1. ?????????????????????????????????????
???rad/s?7.27?10?6rad/s?????????????????
???????v1??R?465.28m/s??????????????????????
?v2??Rcos40?356.43m/s
2. ????????T1?1h???????T2?12h
?1??????????????1??2?T2?T1?12?1
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??????????????????????????????v??r?????????????????????????????
4. ???????????????r1?r2?r3???????????v?
2?r1
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5. ??????????T?0.2s
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1. ??A?????????????an?2???????????????????2????B????????????an?T
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C?????????????an?v?????????????????????????
D?????????????an?v????????????????????????????????????????????????????????
??????????????????????????????????????????
2. ?????????T?27.3243600s?2.36106s????????????
3. ??A?B???????????????????????????????4?3?
???????????4?3????????????????????????3?2????????????3?2????????an?v???????????????2?1???????????????????????????????an?v?? 4. ??(1)???????????????????????????????????
?????????????????????????v1?v2??????????1??2??????????????r1?r2??v1?v2 v1??1r1 v2??2r2???2?n??n1?n2??1??2?r2?r1?3?1 (2)A????????
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?7? ???
1. ?????????????????????????F????????T?
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?????????????????????????????????
2. ??????????????6?19?????????G???????????FN??????????F
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0.16N
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?????????????????????????????????????? 4. ?????????m???A???????r?????????????????
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2r?FT?G?m2
r
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1. ????????????????????F??????????????????
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4
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788????????????????????????????? 2. ?????????????
????????????????????????????????????????????????F?ma?m2
?????????????????vm??
v?m?
/s?18.71m/s?67.35km/h?72km/h????????72km/h??????????????
?????????72km/h???????????????????F?
v210?202v?m?2.0?3
mN?1.6?104N?1.4?104r50
N
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3. ?:?1???????????????G????FN??????????
G?FN?m2???????FN?G?m2?(800?9.8?800?2)N?7440N ??????????????????????7440N?
(2)??????????????????FN?0???????v?
?3???????????????G????FN??????????G?FN?m2???????FN?G?m2?????????????????????????????????????
?4????????????????v0?
4. ?????????m?????????????l???????????????v?
????????????FN????????????0?????????????
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mv
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??FN?mg?1+2(1?cos60)??2mg?2259.8N?490N
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5. ?????????m??????????????????v??????????
FN??????????????????0???????????????????
?????mg(h?2R)?mv2 ?????????FN?mg?m2
R
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(mg?FN)
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7
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1. ????????????????????????????
2. ????????????????????????????????
3. ??????????????r1??????T1??????????r2??????
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4. ???????????
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1. ???????????????????????????????????????
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32. ????????????????????????T
2?k?????????????????????????? ?3????????
1. ????????????60kg???1m???????????????
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F?Gm1m2?114030r10?2?6.67?(5?104?3.0?108?365?24?3600)
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N?1.19?1026N????????????????
m303. ??F?G1m2(7.1?10?r?6.67?10?11
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1. ??:???????G
M?m
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m/s2?1.68m/s2 ??1.7332
g
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2. ?:???????????m?????G
M?m
R?mg???g?GM?
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R? ???????????????????,?????????????m???
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3. ?:??????????????????????????????Gr
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2
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?5??????
1. ????5????????????????????????Gr2
?m(
T)2r
r?
????T??2460??260+37??/14min?91.64min,??
r??6.7?106m????????h?r?R?6.7106m?6.4106m?3105m?300km?
???????5????????????????????????5?????????????????????????????????????
?????5??????????????343km???????????Gr2?m2
T
2r ???????GR
2
?mg?r?R+h
????????T?2?2??
R?90.6min
2. ????????????????????????????????????????
??GR
2?
m2
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???????GR
2
?mg???GM?R2
g ?????1
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??????G
M1m
R2
?mg1 1 ??????M2????2?????????????g2????????G
M2m
R2
?mg2 2
M22 ??????? 1?R2g1??gM1R222M2?1??2R2?g2???9.8m/s?8.9m/s2 2R2
1g2M110.95
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m
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发表于 2019-9-13 23:46:11