[問題] 做功
在一粗糙平面上,有一木塊(M=2kg)以初速10m/s
前進xm,推向彈簧,求彈簧的最大壓縮量x=?
動摩擦係數Uk=0.5
彈力係數K=200N/m
這是我的想法:
1/2MV^2-UkMgx=1/2kx^2
0.5*2*100-0.5*2*9.8x=0.5*200*x^2
100x^2+9.8x-100=0
這樣算對嗎?
如果是對的話,x該怎麼找?
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