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߿ޱ߽ǿų˶طԾϻ
һޱ߽ǿų˶1רѵ
1ͼʾΪųı߽磬Ű뾶ΪRİԲǿųŸӦǿΪBֱֽԲOΪϵһ㣬ҲſΪRǿųֱֽ⡣ΪmΪqĴӣԲϵAijһٶذ뾶ԲδųǡôDAOֱODӴԲϵC㣬ͬijٶų֪AOC=53㣬ӸպܴҲųsin53=0.8cos53=0.6 (1)ӵijٶȼAD˶ʱ䣻
(2)ӴC䣬һ˶ųı߽ʱٶȵķOľ룻 (3)ҲųĴŸӦǿȡ
𰸡(1)v0?(3)B2?1.6B ⡿
?mqBRt?(2)ٶȵķų߽ļнΪ53㣬0.6R
2qBm(1)ӴAųDų켣ͼ
ɼιϵù뾶
r1?R
ṩԲ˶
2mv0 qv0B?m
v0?ڴų˶ԲĽΪ90㣬
qBR mT 4t?Ϊ
T?
2?r1 v0t?(2)ӴC䣬켣ͼ
?m2qB
ɼ֪ʶEFij
LEF=Rcos53
EFO1У
sin??LEF?0.6 RתԲĽ??37?ٶȵķų߽ļнΪ53 CEij
LCE?R?Rcos37?
OFijΪ
LOF?Rsin53??LCE
LOF?0.6R
(3)Ҳųİ뾶Ϊr2ɼιϵ
r2sin37??r2?R
ʽ
2mv0qv0B2?
r2
B2?1.6B
2ͼֽڵľ ABCD ֱǿ糡ǿųԱ ABCDADBC糡ƽֽ棬ųֱֽ棬ŸӦǿȴСΪ B.һӴAB ϵ P ƽֽ䷽ AB ļнΪ ȣ<90㣩ǡֱ˶ CD ȥ糡ͬٶȴP ǡֱ CD .֪߳ AD=BC=dӵΪ mΪ qӵ.
(1)ٶȵĴС
(2)ھֱ˶ʱ䣻 (3)ǿ糡ĵ糡ǿȴС
mcos?qBdqB2d𰸡12 3
qBsin?mcos?mcos?
ӵĹ켣ͼɼιϵ˶İ뾶ţٵڶзٶȵĴСھֱ˶λƿʱ䣻ݵ糡ƽⳡǿ. ⡿
1 賷ȥ糡ʱڴųԲ˶İ뾶ΪR˶켣ͼʾ켣ԲΪO
ɼιϵ֪cos??d R2v0 qv0B?mRv0?qBd mcos?d x2ھֱ˶λΪxsin??˶x=v0t t?mcos?
qBsin?3ھֱ˶ʱ糡ƽ⣺Eq=qv0B
qB2dE?
mcos?㾦
ؼܸӵ˶˶Ĺ켣ͼϼιϵ뾶ֱ֪˶ڵ糡.
3ͼʾAװдͬΪ+qӣӴ·СS1Ʈٵ糡ٶȿΪ㣩ֱ˶ͨСS2ƽа봹ֱ糡ƫת糡ͨƽаֱųŸӦǿΪBֱֽˮƽǿųڸйƬϡ֪ٵ糡S1S2ļٵѹΪUƫת糡峤Ϊ3LΪL糡ǿ糡糡ǿ
E?2UZˮƽĵ糡ƽаf¶ųˮƽ߽ab3LڵPڱ߽abʵߴ̶øйƬôAݳӾڸйƬPQ֮䣬PQijΪ3L߽ab·ĴųΧ㹻