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【!"6#$%·!"#$%& &1
'((2')】
'()*+,-.6/01·!"
#$%&、2345678
1.A )*+,-./01,,-.234,567,-.89:4;,<= A.
2.D >4?5@AB4?CDE,FA7犲=1.6×10-19C,GH4?CAB4?I5>4?,< AJK;LM24NB
4?COP5>4?BQRS,TPUVWRX,<BJK;>4?54?CB@ADE,YZ[\C,4;52M>4
?FA4?CB][^;,_`abTc,< CJK;de[\fghijklmn]o@pqr%s:>4?BR
X,<D3r.
3.B tuv,wBxy+[NBEzxy{|},w 犉~[N3,AJK;uv,w 犉~[N7 犠 =
犉犾cos150°=-犉犾cos30°,uv,w犉~[N7犠 =犉犾cos30°,uuv,w犉~[NTc,B3r,
CJK;tuv,w犉~[N7犠t =犉犾cos30°,tuuv,w犉~[NTc,DJK.
4.D A
犃犅Blv,w3,wPA,AJK;wPBCO+wM,+
5,BJK; A,U7wPP ,A
¡犃BwP¢£犅Bw
PF,CJK,D3r.
5.C ¤4?¥¦1§4?C7-犙+3犙=+2犙,4?¢¨1©2+犙.ª«¬E1,®¯wFA7犉=犽犙·犙
犱2=犽犙2
犱2,
<=C.
6.D "~°±²³´BT24µN犃犅¶·¥¦,¸¹±².º234B24N犆z»µN犃、犅,234B24N
犆¼µN犃、犅vB½4;¾¿ÀÁ,ÀÁÂ4;2Ã4,ÄÁÅ4;234,¨ÆµN犃犅,µN犃Â4;2Ã
4,µN犅Å4;234,ÇzÆ24N犆,µN犃ÈÉ2Ã4,µN犅ÈÉ234,D3r.
7.A jÊËPs\M犠犉+犠犳-犿犵犺=0,犠犉+犠犳=犿犵犺,ÌÍw犉+/0w~[ÎÏ7犿犵犺,< AJK;
6[ÎÐÑÒÓ,jÊËPs\Ôw~[Î7,<B3r;/0w~[Î7犠犳=-μ犿犵cosθ· 犺
sinθ,<
C3r;[ÎËPT,wPÕF,ÖרPÕF,<D3r.
8.BD jÊÙW,4?C7+狇BÚÛ4?¡犆ÜBÝ4wxyÞßZ犃犅y,Ö狇1、
狇2"s2cà34?,A
JK,B3r;ZÚÛ4?¡犆ÜBÝ4wxyÞßZ犃犅y,jÊáâãäåsÖ,tan37°=犉犃犆
犉犅犆=
犽狇1狇
(犃犆)
2
犽狇2狇
(犅犆)
2
,67tan37°=犅犆
犃犆,æiçè狇1
狇2=4
3,CJK,D3r.
9.BC áéêË¡ëßxyÒ½ìNêË,Ö犺=1
2犵狋2,í
îïð1、2êËñòó,ô!õc,Öw
Bá¢öc,ì÷øòBøñö犘=犿犵狏狔,Öì÷øòBøñöc,AJK,B3r;ùáxyM狓=
狏0狋,Z狓2>狓1,
狋1=狋2,6·狏20>狏10,ôwc,ÖËPs\,ì÷øòí
îïð1êËBËPAZî
ïð2êËBËP,C3r,DJK.
10.AD jÊËPs\è Δ犈k=犉Ô Δ犺,Ö犈k犺uúBûö±~XüýÔwBFA,ÖÒÓlM犉Ô =犿犵+犳=
Δ犈1
Δ犺1=72-36
3
N=12N,ìlM犉′Ô =犿犵-犳=Δ犈2
Δ犺2=48-24
3
N=8N,æiçè犳=2N,犿=1kg,ôÒÓuú
,þ+ÿ!B"¡犺=6m,<= A、D.
11.(1)A (2)犿犵犔4 犿(犔5-犔3)
2犳
2
8
(#$2¨)
ç%:(1)7A/0ó&w,'()*ñ+ñ¤,E-./0ëß,A3r;71P2°32,.4¥k4516
ª32,76ª328.9[:)*ñ+1C»";,B、CJK;°½ìNêË<=*>32ÒL=UB*R
BøñÑõ,Ì?@:רPAÍ,DJK.
(2)wPBACΔ犈p=犿犵犔4,32ÒB*RòñòòC犜=1
犳,Ö) 犇ñ[BÑõ狏犇=狓犗犈-狓犗犆
2犜
=
(犔5-犔3)
2
犳
=(犔5-犔3)犳
2
,ÖËPÕDCΔ犈k=犿(犔5-犔3)
2犳
2
8
.(E:°犔6-犔2F*>狏犇GH¨)
12.(1)犱
狋2 (2)P (3)(犕-犿)犵犺=1
2(犿+犕)犱2
狋2
2-犱2
狋
(
)
2
1
(4)B(#$2¨)
ç%:(1)I犃JlK4L2ñ,ZMKNOõ犱PA,QRñòSBá¢Ñõ»TóZøñÑõ,LUI犃J
lK4L2ñÑõBFA7狏2=犱
狋2.
(2)PV{]o,¨¤WXâ]o,4¡K4L1BEYZ[,G[\K4L¡1EÒñI犃JlK4LBñ
ò狋1,É1ºK4LzK4L2BE,Ç[\K4L¡2EÒñI犃JlK4LBñò狋2,ǰ]^C_K
4L1、2EòB!õ`犺Ì.
(3)I犃JlK4L1ñÑõBFA7狏1=犱
狋1,I犃4L1a4L2Blv,bcwPBÅC7
【!"6#$%·!"#$%& &2
'((2')】
Δ犈p=(犕-犿)犵犺,bcËPBÕDC7Δ犈k=1
2(犿+犕)狏2
2-1
2(犿+犕)狏2
1=1
2(犿+犕)犱2
狋2
2-犱2
狋
(
)
2
1
,dbcרPA
Í,ÖΔ犈p=Δ犈k,Ì(犕-犿)犵犺=1
2(犿+犕)犱2
狋2
2-犱2
狋
(
)
2
1
.
(4)e¡$f&wñ,bcgh$f&w,i9bcÅBwP"j¨k7SP,µlbcÅBwP
mFZbcÕDBËP,< AJK;!õ`犺B%CXnA,i9*>_BwPÅCnA,opbcÅBw
P.AZbcÕDBËP,<B3r;MKNOõ犱B%CXnA,i9*>_BÑõnA,q9bcÕDBËP
nA,opbcÅBwP.FZbcÕDBËP,<CJK.
13.ç:(1)A
犅234 (2¨)
(2)~A
Üw¨%,ruLý
ásNtM犜=犿犵cos30° (2¨)
çè犜=槡3
2犿犵 (2¨)
(3)ásNt,èsin30°=犉®
犿犵 (2¨)
®¯s=M犉® =犽狇
2
狓2 (2¨)
æiè#uA
L2B4?CFA狇=
犿犵狓2
2
槡犽 (2¨)
14.ç:(1)ÙWvwÜB&w7犳=1
10犿犵=2000N (1¨)
85sS~vwÜw¨%,xy&_s=M犉-犳=犿犪 (1¨)
çè犪=2m/s2 (1¨)
(2)5szvwBÑõ狏1=犪狋=10m/s (1¨)
Ö犘{ =犉狏1=6×104W (2¨,|}、~©1¨)
狏max=犘{
犳=30m/s (2¨,|}1¨、~1¨)
(3)ËPs\M犘{狋-犳狊=1
2犿狏2
max (2¨)
çè狊=750m (2¨)
15.ç:(1)[Î犘犃Ý犅,רPAÍs=è犿犵犚(1-cosθ)=1
2犿狏犅
2 (1¨)
çè狏犅=4m/s (1¨)
¡犅,xy&_s=M犉N-犿犵=犿狏2
犅
犚 (1¨)
çè犉N=18N
xy&s=,[Î犘Jl犅ñ~ïBwFA犉′N=犉N=18N (1¨)
(2)犆
@FE
PCAÍs=èμ犿犵狊+犈p=1
2犿狏犆
2 (2¨)
çè狏犆=6m/s (1¨)
@FEyÀêË
PCAÍs=,èμ犿犵狊′=犈p (1¨)
çè狊′=1.6m<2m (1¨)
Ö[Î犘@BE犆B:7狊-狊′=0.4m (1¨)
(3)6狏犅<狏犆,<[Ρ2ÒiDÑ
[Î"ßDÑ,ÖËPs\Mμ犿犵犔=1
2犿狏犆′-1
2犿狏2
犅
çè狏犆′
槡
=46m/s>狏犆
Ö[Ρ2Ò4DÑ1+2(Ñ,Ì2BÑö狏=狏犆=6m/s (1¨)
[Ρ2ÒBDÑõ犪=μ犵=5m/s2 (1¨)
[Ρ2ÒBDÑñò狋=狏犆-狏犅
犪
=2
5s (1¨)
Ö[Î+2ÏòB~Ez7狓~ =狏犆狋-狏犅+狏犆
2
·狋=2
5m (1¨)
PCAÍs=è4Ë×~2ÂB7犠犳+Δ犈k=μ犿犵狓~ +1
2犿狏2
犆-1
2犿狏2
犅=12J (2¨)