题干

如图,汽车沿平直路面向右做匀变速直线运动,质量为m的小球A用细线悬挂在车顶上,若观察到细线偏离竖直方向θ角,则下列说法正确的是(   )

A:汽车向右做匀加速运动,加速度大小是gtanθ

B:汽车向右做匀减速运动,加速度大小是gtanθ

C:汽车做匀速运动,加速度是0

D:细线的拉力是 mgcosθ

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答案(点此获取答案解析)

B,D

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