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力的分解

> 水平地面上斜放着一块木板AB，如图所示，在木板上放一木块处于静止状态，现使斜面的B端缓慢的降低（即使斜面的倾角缓慢的减小），则在此过程中木块所受弹力N，摩擦力f的变化情况是（） A．N增大，f减小 B．N减小，f增大 C．N减小，f减小 D．N增大，f增大

问题：

发布时间：2024-09-13

水平地面上斜放着一块木板AB，如图所示，在木板上放一木块处于静止状态，现使斜面的B端缓慢的降低（即使斜面的倾角缓慢的减小），则在此过程中木块所受弹力N，摩擦力f的变化情况是（）

A．N增大，f减小 B．N减小，f增大

C．N减小，f减小 D．N增大，f增大

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