不定项选择题:16.由于卫星的发射场不在赤道上,同步卫星发射后需要从转移轨道经过调整再进入地球同步轨道。当卫星在转移轨道上飞经赤道上空

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题目内容:
16.由于卫星的发射场不在赤道上,同步卫星发射后需要从转移轨道经过调整再进入地球同步轨道。当卫星在转移轨道上飞经赤道上空时,发动机点火,给卫星一附加速度,使卫星沿同步轨道运行。已知同步卫星的环绕速度约为3.1x103/s,某次发射卫星飞经赤道上空时的速度为1.55x103/s,此时卫星的高度与同步轨道的高度相同,转移轨道和同步轨道的夹角为30°,如图所示,发动机给卫星的附加速度的方向和大小约为
A.西偏北方向,1.9x103m/s
B.东偏南方向,1.9x103m/s
C.西偏北方向,2.7x103m/s
D.东偏南方向,2.7x103m/s
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