[領域]衝量

[來源]動力學課本習題

[題目]The 250-N cabinet is subjected to the force F=10/(t+1) N where t s in
seconds.If the cabinet is initially moving down the plane wuth a velocity of
3m/s,determine how long it will take before the cabinet comes to a stop F
always acts parallel to the plane.(圖片是一個櫃子在20度的斜面上)

[瓶頸]
我的列式是(250/9.8)(-3)+10ln(t+1)-250*t*sin20=0
可是解不出來= =
後來想想F=10/(t+1) t就算是趨近0 都會小mgsin20 這樣子加速度都會往下
怎麼會停止勒@@" 我有想錯嗎?這題目的課本解答是0.974秒

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